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ITEM 8—FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549

FORM 10-K

Commission file number 1-35015

ACNB CORPORATION
(Exact name of registrant as specified in its charter)

Registrant's telephone number, including area code: (717) 334-3161

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

         Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes o    No ý

         Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes o    No ý

         Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý    No o

         Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes ý    No o

         Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of the registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ý

         Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act. (Check One)

         If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

         Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes o    No ý

         The aggregate market value of the voting stock held by nonaffiliates of the registrant at June 30, 2017, was approximately $208,794,290.

         The number of shares of the registrant's common stock outstanding on March 9, 2018, was 7,023,658.

         Documents Incorporated by Reference

         Portions of the registrant's 2018 definitive Proxy Statement are incorporated by reference into Part III of this report.

   

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ACNB CORPORATION

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PART I

FORWARD-LOOKING STATEMENTS

        In addition to historical information, this Form 10-K contains forward-looking statements. Examples of forward-looking statements include, but are not limited to, (a) projections or statements regarding future earnings, expenses, net interest income, other income, earnings or loss per share, asset mix and quality, growth prospects, capital structure, and other financial terms, (b) statements of plans and objectives of management or the Board of Directors, and (c) statements of assumptions, such as economic conditions in the Corporation's market areas. Such forward-looking statements can be identified by the use of forward-looking terminology such as "believes", "expects", "may", "intends", "will", "should", "anticipates", or the negative of any of the foregoing or other variations thereon or comparable terminology, or by discussion of strategy. Forward-looking statements are subject to certain risks and uncertainties such as local economic conditions, competitive factors, and regulatory limitations. Actual results may differ materially from those projected in the forward-looking statements. Such risks, uncertainties and other factors that could cause actual results and experience to differ from those projected include, but are not limited to, the following: the effects of governmental and fiscal policies, as well as legislative and regulatory changes; the effects of new laws and regulations, specifically the impact of the Tax Cuts and Jobs Act and the Dodd-Frank Wall Street Reform and Consumer Protection Act; impacts of the new capital and liquidity requirements of the Basel III standards; the effects of changes in accounting policies and practices, as may be adopted by the regulatory agencies, as well as the Financial Accounting Standards Board and other accounting standard setters; ineffectiveness of the business strategy due to changes in current or future market conditions; future actions or inactions of the United States government, including the effects of short-and long-term federal budget and tax negotiations and a failure to increase the government debt limit or a prolonged shutdown of the federal government; the effects of economic deterioration and the prolonged economic malaise on current customers, specifically the effect of the economy on loan customers' ability to repay loans; the effects of competition, and of changes in laws and regulations on competition, including industry consolidation and development of competing financial products and services; the risks of changes in interest rates on the level and composition of deposits, loan demand, and the values of loan collateral, securities, and interest rate protection agreements, as well as interest rate risks; difficulties in acquisitions and integrating and operating acquired business operations, including information technology difficulties; challenges in establishing and maintaining operations in new markets; the effects of technology changes; volatilities in the securities markets; the effect of general economic conditions and more specifically in the Corporation's market area; the failure of assumptions underlying the establishment of reserves for loan losses and estimations of values of collateral and various financial assets and liabilities; acts of war or terrorism; disruption of credit and equity markets; the ability to manage current levels of impaired assets; the loss of certain key officers; the ability to maintain the value and image of the Corporation's brand and protect the Corporation's intellectual property rights; continued relationships with major customers; and, potential impacts to the Corporation from continually evolving cybersecurity and other technological risks and attacks, including additional costs, reputational damage, regulatory penalties, and financial losses. We caution readers not to place undue reliance on these forward-looking statements. They only reflect management's analysis as of this date. The Corporation does not revise or update these forward-looking statements to reflect events or changed circumstances. Please carefully review the risk factors described in other documents the Corporation files from time to time with the Securities and Exchange Commission, including the Quarterly Reports on Form 10-Q and any Current Reports on Form 8-K.

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ITEM 1—BUSINESS

ACNB CORPORATION

        ACNB Corporation (the Corporation or ACNB), headquartered in Gettysburg, Pennsylvania, is the financial holding company for the wholly-owned subsidiaries of ACNB Bank, Gettysburg, Pennsylvania, and Russell Insurance Group, Inc. (RIG), Westminster, Maryland. Originally founded in 1857, ACNB Bank serves its marketplace with banking and wealth management services, including trust and retail brokerage, via a network of 22 community banking offices located in the four southcentral Pennsylvania counties of Adams, Cumberland, Franklin and York, as well as one loan production office in York County, Pennsylvania. In addition, NWSB Bank, a division of ACNB Bank, serves its marketplace via a network of seven community banking offices located in Carroll County, Maryland. RIG, the Corporation's insurance subsidiary, offers a broad range of commercial and personal insurance lines through offices in Westminster, Carroll County, and Germantown, Montgomery County, Maryland.

        ACNB Corporation was formed in 1982, then became the holding company for Adams County National Bank (now ACNB Bank) in 1983. The Corporation purchased RIG, its insurance subsidiary, in 2005. And, effective July 1, 2017, ACNB Corporation completed the acquisition of New Windsor Bancorp, Inc. and its wholly-owned subsidiary, New Windsor State Bank, a Maryland state-chartered, FDIC-insured community bank headquartered in Taneytown, Maryland.

        ACNB's major source of unconsolidated operating funds is dividends that it receives from its subsidiaries. ACNB's expenses consist principally of losses from low-income housing investments, as well as interest paid in 2015 on a term loan for the purchase of RIG that was paid off in July 2015. Dividends that ACNB pays to stockholders consist of dividends declared and paid to ACNB by the subsidiary bank.

        ACNB and its subsidiaries are not dependent upon a single customer or a small number of customers, the loss of which would have a material adverse effect on the Corporation. ACNB does not depend on foreign sources of funds, nor does it make foreign loans.

        The common stock of ACNB is listed on The NASDAQ Capital Market under the symbol ACNB.

New Windsor Bancorp, Inc. Acquisition

        On July 1, 2017, ACNB completed its acquisition of New Windsor Bancorp, Inc. (New Windsor), a bank holding company based in Taneytown, Maryland. In addition, New Windsor State Bank, a Maryland state-chartered bank and New Windsor's wholly-owned subsidiary, merged with and into ACNB Bank. The acquisition was valued at $33.3 million and resulted in ACNB issuing $4.5 million in cash and 938,360 shares to New Windsor shareholders.

BANKING SUBSIDIARY

ACNB Bank

        ACNB Bank is a full-service commercial bank operating under charter from the Pennsylvania Department of Banking and Securities. The Bank's principal market areas include Adams County, Pennsylvania, and its environs in southcentral Pennsylvania, as well as Carroll County, Maryland, in northern Maryland. This geographic area depends on agriculture, industry, tourism, education and healthcare to provide employment for its residents. No single sector dominates the area's economy. At December 31, 2017, ACNB Bank had total assets of $1,584,000,000, total gross loans of $1,244,000,000, total deposits of $1,584,000,000, and total equity capital of $143,000,000. In October 2010, the Bank converted from a national banking association to a Pennsylvania state-chartered bank and trust company.

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        The main community banking office of the Bank is located at 16 Lincoln Square, Gettysburg, Pennsylvania. In addition to its main office, as of December 31, 2017, the Bank has 13 community banking offices in Adams County, five community banking offices in York County, one community banking office in Cumberland County, and two community banking offices in Franklin County, as well as a loan production office in York County, Pennsylvania. In Maryland, ACNB Bank operated seven community banking offices in Carroll County branded as NWSB Bank, a division of ACNB Bank. The Bank's service delivery channels for its customers also include the ATM network, Customer Contact Center, and Online, Telephone and Mobile Banking. The Bank is subject to regulation and periodic examination by the Pennsylvania Department of Banking and Securities and the Federal Deposit Insurance Corporation (FDIC). The FDIC, as provided by law, insures the Bank's deposits.

        Commercial lending includes commercial mortgages, real estate development and construction loans, accounts receivable and inventory financing, and agricultural and governmental loans. Consumer lending programs include home equity loans and lines of credit, automobile and recreational vehicle loans, manufactured housing loans, and personal lines of credit. Mortgage lending programs include personal residential mortgages, residential construction loans, and investment mortgage loans.

        A trust is a legal fiduciary agreement whereby ACNB Bank, through its Trust & Investment Services function, is named as trustee of financial assets. As trustee, ACNB Bank invests, protects, manages and distributes financial assets as defined in the agreement. Estate settlement governed by the last will and testament of an individual constitutes another line of business for ACNB Bank Trust & Investment Services. One purpose of having a will is to name an executor to settle the estate. ACNB Bank has the knowledge and expertise to act as executor. Other services include, but are not limited to, those related to testamentary trusts, life insurance trusts, charitable remainder trusts, guardianships, powers of attorney, custodial accounts, and investment management and advisory accounts. Total trust assets under management were $224,000,000 at December 31, 2017.

        In addition to ACNB Bank Trust & Investment Services, under the umbrella of ACNB Wealth Management, ACNB offers retail brokerage services through a third-party provider as a result of the acquisition of New Windsor State Bank effective July 1, 2017. This third-party provider is a broker/dealer, unaffiliated with ACNB Bank. At December 31, 2017, total assets under management with the broker/dealer were $103,000,000.

NONBANKING SUBSIDIARIES

Russell Insurance Group, Inc.

        ACNB Corporation's wholly-owned subsidiary, Russell Insurance Group, Inc. (RIG), is a full-service insurance agency that offers a broad range of property and casualty, life, and health insurance to both commercial and individual clients with licenses in 44 states. Based in Westminster, Maryland, RIG has served the needs of its clients since its founding as an independent insurance agency by Frank C. Russell, Jr. in 1978. The agency was purchased by the Corporation in 2005. RIG operates a second office location in Germantown, Maryland. Total assets of RIG as of December 31, 2017, were $9,368,000.

        RIG is managed separately from the banking and related financial services that the Corporation offers and is reported as a separate segment. Financial information on this segment is included in the Notes to Consolidated Financial Statements, Note S—"Segment and Related Information".

MARKET AREA ECONOMIC FEATURES AND CONDITIONS

        ACNB Corporation's major operations are in the more rural areas of the Harrisburg-Carlisle MSA and the York-Hanover MSA in Pennsylvania, along with all of Adams County, Pennsylvania, parts of Franklin County, Pennsylvania, and all of Carroll County, Maryland. Approximately 60% of the

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population resides in areas designated rural. Major types of employers include those focused on manufacturing, education, healthcare, agriculture, tourism, and transportation/warehousing, as well as local governments. A material amount of land surrounding Gettysburg, Pennsylvania, is under the control of the National Park Service, limiting certain types of development. Unemployment figures in the subsidiary bank's market recently, and historically, have been better than those for Pennsylvania and the United States. Per capita and household incomes are generally under Pennsylvania averages. The unemployment rate averaged 3.74% in the subsidiary bank's five-county marketplace, while it was 4.70% overall in Pennsylvania and 4.10% in the United States.

COMPETITION

        The financial services industry in ACNB's market area is highly competitive, including competition for similar products and services from commercial banks, thrifts, credit unions, finance and mortgage companies, and other nonbank providers of financial services. Several of ACNB's competitors have legal lending limits that exceed those of ACNB's subsidiary bank, as well as funding sources in the capital markets that exceed ACNB's availability. The high level of competition has resulted from changes in the legal and regulatory environment, as well as from the economic climate, customer expectations, and service alternatives via the internet. There are 91 publicly-traded banks in Pennsylvania and Maryland, 17 have greater market share than ACNB. In addition, there are 17 thrift institutions and numerous credit unions in Pennsylvania and Maryland, some with greater market share.

SUPERVISION AND REGULATION

Regulation of Bank Holding Company and Subsidiaries

        BANK HOLDING COMPANY ACT OF 1956—ACNB is a financial holding company and is subject to the regulations of the Board of Governors of the Federal Reserve System under the Bank Holding Company Act of 1956. Bank holding companies are required to file periodic reports with and are subject to examination by the Federal Reserve.

        The Federal Reserve has issued regulations under the Bank Holding Company Act that require a financial holding company to serve as a source of financial and managerial strength to its subsidiary bank. As a result, the Federal Reserve may require ACNB to stand ready to use its resources to provide adequate capital funds to the Bank during periods of financial stress or adversity. In addition, the Federal Reserve may require a financial holding company to end a nonbanking business if the nonbanking business constitutes a serious risk to the financial soundness and stability of any banking subsidiary of the financial holding company.

        The Bank Holding Company Act prohibits ACNB from acquiring direct or indirect control of more than 5% of the outstanding voting stock of any bank, or substantially all of the assets of any bank, or merging with another bank holding company, without the prior approval of the Federal Reserve. The Bank Holding Company Act allows interstate bank acquisitions and interstate branching by acquisition and consolidation in those states that had not elected to opt out by the required deadline. The Pennsylvania Department of Banking and Securities also must approve any similar consolidation. Pennsylvania law permits Pennsylvania financial holding companies to control an unlimited number of banks.

        Further, the Bank Holding Company Act restricts ACNB's nonbanking activities to those that are determined by the Federal Reserve Board to be financial in nature, incidental to such financial activity, or complementary to a financial activity. The Bank Holding Company Act does not place territorial restrictions on the activities of nonbanking subsidiaries of financial holding companies.

        GRAMM-LEACH-BLILEY ACT OF 1999 (GLBA)—The Gramm-Leach-Bliley Act of 1999 eliminated many of the restrictions placed on the activities of bank holding companies that become

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financial holding companies. Among other things, the Gramm-Leach-Bliley Act repealed certain Glass-Steagall Act restrictions on affiliations between banks and securities firms, and amended the Bank Holding Company Act to permit bank holding companies that are financial holding companies to engage in activities, and acquire companies engaged in activities, that are: financial in nature (including insurance underwriting, insurance company portfolio investment, financial advisory, securities underwriting, dealing and market-making, and merchant banking activities); incidental to financial activities; or, complementary to financial activities if the Federal Reserve determines that they pose no substantial risk to the safety or soundness of depository institutions or the financial system in general.

        REGULATION W—Transactions between a bank and its "affiliates" are quantitatively and qualitatively restricted under the Federal Reserve Act. The Federal Deposit Insurance Act applies Sections 23A and 23B to insured nonmember banks in the same manner and to the same extent as if they were members of the Federal Reserve System. The Federal Reserve has also issued Regulation W, which codifies prior regulations under Sections 23A and 23B of the Federal Reserve Act, and interpretative guidance with respect to affiliate transactions. Regulation W incorporates the exemption from the affiliate transaction rules, but expands the exemption to cover the purchase of any type of loan or extension of credit from an affiliate. Affiliates of a bank include, among other entities, the bank's holding company and companies that are under common control with the bank. ACNB Corporation and Russell Insurance Group, Inc. are considered to be affiliates of ACNB Bank.

        USA PATRIOT ACT OF 2001 (Patriot Act)—In October 2001, the USA Patriot Act of 2001 was enacted in response to the terrorist attacks in New York, Pennsylvania and Washington, D.C., which occurred on September 11, 2001. The Patriot Act is intended to strengthen U.S. law enforcement's and the intelligence communities' abilities to work cohesively to combat terrorism on a variety of fronts. The impact of the Patriot Act on financial institutions of all kinds is significant and wide ranging. The Patriot Act contains sweeping anti-money laundering and financial transparency laws and imposes various regulations, including standards for verifying customer identification at account opening, and rules to promote cooperation among financial institutions, regulators and law enforcement entities in identifying parties that may be involved in terrorism or money laundering.

        SARBANES-OXLEY ACT OF 2002 (SOA)—In 2002, the Sarbanes-Oxley Act of 2002 became law. The stated goals of the SOA are to increase corporate responsibility, to provide for enhanced penalties for accounting and auditing improprieties at publicly-traded companies, and to protect investors by improving the accuracy and reliability of corporate disclosures pursuant to the securities law.

        The SOA generally applies to all companies, both U.S. and non-U.S., that file or are required to file periodic reports with the Securities and Exchange Commission (SEC) under the Securities Exchange Act of 1934, or the Exchange Act.

        The SOA includes very specific additional disclosure requirements and corporate governance rules, as well as requires the SEC and securities exchanges to adopt extensive additional disclosure, corporate governance, and other related rules. The SOA represents significant federal involvement in matters traditionally left to state regulatory systems, such as the regulation of the accounting profession, and to state corporate law, such as the relationship between a board of directors and management and between a board of directors and its committees.

        The SOA addresses, among other matters:

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Audit committees for all reporting companies;



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Certification of financial statements by the chief executive officer and the chief financial officer;

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The forfeiture of bonuses or other incentive-based compensation and profits from the sale of an issuer's securities by directors and senior officers in the twelve-month period following initial publication of any financial statements that later require restatement;



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A prohibition on insider trading during pension plan blackout periods;



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Disclosure of off-balance sheet transactions;



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A prohibition on personal loans to directors and officers;



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Expedited filing requirements for SEC Forms 4;



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Disclosure of a code of ethics and filing an SEC Form 8-K for a change or waiver of such code;



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"Real time" filing of periodic reports;



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Formation of a public accounting oversight board;



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Auditor independence; and,



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Increased criminal penalties for violations of securities laws.

        The SEC has been delegated the task of enacting rules to implement various provisions of the SOA with respect to, among other matters, disclosure in periodic filings pursuant to the Exchange Act.

        TAX CUTS AND JOBS ACT—On December 22, 2017, the Tax Cuts and Jobs Act was signed into law. Among other changes, the Tax Cuts and Jobs Act reduces the federal corporate tax rate from 35% to 21% effective January 1, 2018. ACNB anticipates that this tax rate change should reduce its federal income tax liability in future years beginning with 2018. However, the Corporation did recognize certain effects of the tax law changes in 2017. U.S. generally accepted accounting principles require companies to re-value their deferred tax assets and liabilities as of the date of enactment, with resulting tax effects accounted for in the reporting period of enactment. Since the enactment took place in December 2017, the Corporation revalued its net deferred tax assets in the fourth quarter of 2017, resulting in an approximately $1.7 million reduction to earnings in 2017.

        AMERICAN JOBS CREATION ACT OF 2004—In 2004, the American Jobs Creation Act was enacted as the first major corporate tax act in years. The act addresses a number of areas of corporate taxation including executive deferred compensation restrictions. The impact of the act on ACNB is not material.

        BANK SECRECY ACT (BSA)—Under the Bank Secrecy Act, banks and other financial institutions are required to report to the Internal Revenue Service currency transactions of more than $10,000 or multiple transactions of which a bank is aware in any one day that aggregate in excess of $10,000 and to report suspicious transactions under specified criteria. Civil and criminal penalties are provided under the BSA for failure to file a required report, for failure to supply information required by the BSA, or for filing a false or fraudulent report.

        DODD-FRANK WALL STREET REFORM AND CONSUMER PROTECTION ACT (DODD-FRANK)—In 2010, the Dodd-Frank Wall Street Reform and Consumer Protection Act was signed into law. Dodd-Frank was intended to effect a fundamental restructuring of federal banking regulation. Among other things, Dodd-Frank created the Financial Stability Oversight Council to identify systemic risks in the financial system and gives federal regulators new authority to take control of and liquidate financial firms. Dodd-Frank additionally created a new independent federal regulator to administer federal consumer protection laws. Dodd-Frank has had and will continue to have a significant impact on ACNB's business operations as its provisions take effect. It is expected that, as various implementing rules and regulations are released, they will increase ACNB's operating and

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compliance costs and could increase the Bank's interest expense. Among the provisions that are likely to affect ACNB are the following:

Holding Company Capital Requirements

        Dodd-Frank requires the Federal Reserve to apply consolidated capital requirements to bank holding companies that are no less stringent than those currently applied to depository institutions. Under these standards, trust preferred securities are excluded from Tier 1 capital unless such securities were issued prior to May 19, 2010, by a bank holding company with less than $15 billion in assets as of December 31, 2009. Dodd-Frank additionally requires that bank regulators issue countercyclical capital requirements so that the required amount of capital increases in times of economic expansion, consistent with safety and soundness. For further information, please refer to Regulatory Capital Changes in Management's Discussion and Analysis.

Deposit Insurance

        Dodd-Frank permanently increased the maximum deposit insurance amount for banks, savings institutions, and credit unions to $250,000 per depositor. Dodd-Frank also broadens the base for FDIC insurance assessments. Assessments are now based on the average consolidated total assets less tangible equity capital of a financial institution. Dodd-Frank requires the FDIC to increase the reserve ratio of the Deposit Insurance Fund from 1.15% to 1.35% of insured deposits by 2020 and eliminates the requirement that the FDIC pay dividends to insured depository institutions when the reserve ratio exceeds certain thresholds. Dodd-Frank also eliminated the federal statutory prohibition against the payment of interest on business checking accounts.

Corporate Governance

        Dodd-Frank requires publicly-traded companies to give stockholders a non-binding vote on executive compensation at least every three years, a non-binding vote regarding the frequency of the vote on executive compensation at least every six years, and a non-binding vote on "golden parachute" payments in connection with approvals of mergers and acquisitions unless previously voted on by stockholders. Additionally, Dodd-Frank directs the federal banking regulators to promulgate rules prohibiting excessive compensation paid to executives of depository institutions and their holding companies with assets in excess of $1.0 billion, regardless of whether the company is publicly traded. Dodd-Frank also gives the SEC authority to prohibit broker discretionary voting on elections of directors and executive compensation matters.

Prohibition Against Charter Conversions of Troubled Institutions

        Dodd-Frank prohibits a depository institution from converting from a state to a federal charter, or vice versa, while it is the subject of a cease and desist order or other formal enforcement action or a memorandum of understanding with respect to a significant supervisory matter unless the appropriate federal banking agency gives notice of the conversion to the federal or state authority that issued the enforcement action and that agency does not object within 30 days. The notice must include a plan to address the significant supervisory matter. The converting institution must also file a copy of the conversion application with its current federal regulator, which must notify the resulting federal regulator of any ongoing supervisory or investigative proceedings that are likely to result in an enforcement action and provide access to all supervisory and investigative information relating thereto.

Interstate Branching

        Dodd-Frank authorizes national and state banks to establish branches in other states to the same extent as a bank chartered by that state would be permitted. Previously, banks could only establish branches in other states if the host state expressly permitted out-of-state banks to establish branches in that state. Accordingly, banks are able to enter new markets more freely.

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Limits on Interstate Acquisitions and Mergers

        Dodd-Frank precludes a bank holding company from engaging in an interstate acquisition—the acquisition of a bank outside its home state—unless the bank holding company is both well capitalized and well managed. Furthermore, a bank may not engage in an interstate merger with another bank headquartered in another state unless the surviving institution will be well capitalized and well managed. The previous standard in both cases was adequately capitalized and adequately managed.

Limits on Interchange Fees

        Dodd-Frank amended the Electronic Fund Transfer Act to, among other things, give the Federal Reserve the authority to establish rules regarding interchange fees charged for electronic debit transactions by payment card issuers having assets over $10 billion and to enforce a new statutory requirement that such fees be reasonable and proportional to the actual cost of a transaction to the issuer.

Consumer Financial Protection Bureau

        Dodd-Frank created the independent federal agency called the Consumer Financial Protection Bureau (CFPB), which is granted broad rulemaking, supervisory and enforcement powers under various federal consumer financial protection laws, including the Equal Credit Opportunity Act, Truth in Lending Act, Real Estate Settlement Procedures Act, Fair Credit Reporting Act, Fair Debt Collection Act, Consumer Financial Privacy provisions of the Gramm-Leach-Bliley Act, and certain other statutes. The CFPB has examination and primary enforcement authority with respect to depository institutions with $10 billion or more in assets. Smaller institutions are subject to rules promulgated by the CFPB, but continue to be examined and supervised by federal banking regulators for consumer compliance purposes. The CFPB has authority to prevent unfair, deceptive or abusive practices in connection with the offering of consumer financial products. Dodd-Frank authorizes the CFPB to establish certain minimum standards for the origination of residential mortgages including a determination of the borrower's ability to repay. In addition, Dodd-Frank allows borrowers to raise certain defenses to foreclosure if they receive any loan other than a "qualified mortgage" as defined by the CFPB. Dodd-Frank permits states to adopt consumer protection laws and standards that are more stringent than those adopted at the federal level and, in certain circumstances, permits state attorneys general to enforce compliance with both the state and federal laws and regulations.

        ABILITY-TO-REPAY AND QUALIFIED MORTGAGE RULE—Pursuant to Dodd-Frank as highlighted above, the CFPB issued a final rule on January 10, 2013 (effective on January 10, 2014), amending Regulation Z as implemented by the Truth in Lending Act, requiring mortgage lenders to make a reasonable and good faith determination based on verified and documented information that a consumer applying for a mortgage loan has a reasonable ability to repay the loan according to its terms. Mortgage lenders are required to determine the consumer's ability to repay in one of two ways. The first alternative requires the mortgage lender to consider the following eight underwriting factors when making the credit decision: (1) current or reasonably expected income or assets; (2) current employment status; (3) the monthly payment on the covered transaction; (4) the monthly payment on any simultaneous loan; (5) the monthly payment for mortgage-related obligations; (6) current debt obligations, alimony, and child support; (7) the monthly debt-to-income ratio or residual income; and, (8) credit history. Alternatively, the mortgage lender can originate "qualified mortgages", which are entitled to a presumption that the creditor making the loan satisfied the ability-to-repay requirements. In general, a "qualified mortgage" is a mortgage loan without negative amortization, interest-only payments, balloon payments, or terms exceeding 30 years. In addition, to be a qualified mortgage, the points and fees paid by a consumer cannot exceed 3% of the total loan amount. Loans which meet these criteria will be considered qualified mortgages and, as a result, generally protect lenders from fines or litigation in the event of foreclosure. Qualified mortgages that are "higher-priced"

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(e.g., subprime loans) garner a rebuttable presumption of compliance with the ability-to-repay rules, while qualified mortgages that are not "higher-priced" (e.g., prime loans) are given a safe harbor of compliance. The impact of the final rule, and the subsequent amendments thereto, on the Corporation's lending activities and the Corporation's statements of income or condition has had little or no impact; however, management will continue to monitor the implementation of the rule for any potential effects on the Corporation's business.

        DEPARTMENT OF DEFENSE MILITARY LENDING RULE—In 2015, the U.S. Department of Defense issued a final rule which restricts pricing and terms of certain credit extended to active duty military personnel and their families. This rule, which was implemented effective October 3, 2016, caps the interest rate on certain credit extensions to an annual percentage rate of 36% and restricts other fees. The rule requires financial institutions to verify whether customers are military personnel subject to the rule. The impact of this final rule, and any subsequent amendments thereto, on the Corporation's lending activities and the Corporation's statements of income or condition has had little or no impact; however, management will continue to monitor the implementation of the rule for any potential effects on the Corporation's business.

        FEDERAL DEPOSIT INSURANCE CORPORATION ACT OF 1991—Under the Federal Deposit Insurance Corporation Act of 1991, any depository institution, including the subsidiary bank, is prohibited from paying any dividends, making other distributions or paying any management fees if, after such payment, it would fail to satisfy the minimum capital requirement.

        FEDERAL RESERVE ACT—A subsidiary bank of a bank holding company is subject to certain restrictions and reporting requirements imposed by the Federal Reserve Act, including:

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Extensions of credit to the bank holding company, its subsidiaries, or principal shareholders;



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Investments in the stock or other securities of the bank holding company or its subsidiaries; and,



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Taking such stock or securities as collateral for loans.

        COMMUNITY REINVESTMENT ACT OF 1977 (CRA)—Under the Community Reinvestment Act of 1977, the FDIC is required to assess the record of all financial institutions regulated by it to determine if these institutions are meeting the credit needs of the community, including low- and moderate-income neighborhoods, which they serve and to take this record into account in its evaluation of any application made by any of such institutions for, among other things, approval of a branch or other deposit facility, office relocation, merger, or acquisition of bank shares. The Financial Institutions Reform, Recovery and Enforcement Act of 1989 amended the CRA to require, among other things, that the FDIC make publicly available the evaluation of a bank's record of meeting the credit needs of its entire community, including low- and moderate-income neighborhoods. This evaluation includes a descriptive rating like "outstanding", "satisfactory", "needs to improve" or "substantial noncompliance" and a statement describing the basis for the rating. These ratings are publicly disclosed.

        FEDERAL DEPOSIT INSURANCE CORPORATION IMPROVEMENT ACT OF 1991 (FDICIA)—The Federal Deposit Insurance Corporation Improvement Act requires that institutions be classified, based on their risk-based capital ratios, into one of five defined categories, as follows and as

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illustrated below: well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized, or critically undercapitalized.

        In the event an institution's capital deteriorates to the undercapitalized category or below, FDICIA prescribes an increasing amount of regulatory intervention, including the institution of a capital restoration plan and a guarantee of the plan by a parent institution and the placement of a hold on increases in assets, number of branches, or lines of business. If capital reaches the significantly or critically undercapitalized levels, further material restrictions can be imposed, including restrictions on interest payable on accounts, dismissal of management, and, in critically undercapitalized situations, appointment of a receiver. For well capitalized institutions, FDICIA provides authority for regulatory intervention when the institution is deemed to be engaging in unsafe or unsound practices or receives a less than satisfactory examination report rating for asset quality, management, earnings or liquidity. All but well capitalized institutions are prohibited from accepting brokered deposits without prior regulatory approval. Under FDICIA, financial institutions are subject to increased regulatory scrutiny and must comply with certain operational, managerial and compensation standards established by Federal Reserve Board regulations.

        In July 2013, the federal banking agencies issued final rules to implement the Basel III regulatory capital reforms and changes required by the Dodd-Frank Act. The phase-in period for community banking organizations began January 1, 2015, while larger institutions (generally those with assets of $250 billion or more) began compliance on January 1, 2014. The final rules call for the following capital requirements:

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A minimum ratio of common Tier 1 capital to risk-weighted assets of 4.5%.



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A minimum ratio of Tier 1 capital to risk-weighted assets of 6.0%.



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A minimum ratio of total capital to risk-weighted assets of 8.0%.



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A minimum leverage ratio of 4.0%.

        In addition, the final rules establish a common equity Tier 1 capital conservation buffer of 2.5% of risk-weighted assets applicable to all banking organizations. If a banking organization fails to hold capital above the minimum capital ratios and the capital conservation buffer, it will be subject to certain restrictions on capital distributions and discretionary bonus payments. The phase-in period for the capital conservation and countercyclical capital buffers for all banking organizations began on January 1, 2016.

        A more in-depth discussion of how these new capital rules affect ACNB Corporation appears under Item 7—Management's Discussion and Analysis of Financial Condition and Results of Operations.

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        JUMPSTART OUR BUSINESS STARTUPS ACT (JOBS ACT)—In 2012, the JOBS Act became law. The JOBS Act is aimed at facilitating capital raising by smaller companies and banks and bank holding companies by implementing the following changes:

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Raising the threshold requiring registration under the Securities Exchange Act of 1934 (Exchange Act) for banks and bank holding companies from 500 to 2,000 holders of record;



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Raising the threshold for triggering deregistration under the Exchange Act for banks and bank holding companies from 300 to 1,200 holders of record;



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Raising the limit for Regulation A offerings from $5 million to $50 million per year and exempting some Regulation A offerings from state blue sky laws;



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Permitting advertising and general solicitation in Rule 506 and Rule 144A offerings;



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Allowing private companies to use "crowd funding" to raise up to $1 million in any 12-month period, subject to certain conditions; and,



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Creating a new category of issuer, called an "Emerging Growth Company", for companies with less than $1 billion in annual gross revenue, which will benefit from certain changes that reduce the cost and burden of carrying out an equity initial public offering (IPO) and complying with public company reporting obligations for up to five years.

While the JOBS Act was not expected to have any immediate application to the Corporation, and since 2012 has had no material impact, management will continue to monitor the implementation rules for potential effects which might benefit the Corporation.

Dividends

        ACNB is a legal entity separate and distinct from its subsidiary bank. ACNB's revenues, on a parent company only basis, result primarily from dividends paid to the Corporation by its subsidiaries. Federal and state laws regulate the payment of dividends by ACNB's subsidiary bank. For further information, please refer to Regulation of Bank below.

Regulation of Bank

        The operations of the subsidiary bank are subject to statutes applicable to banks chartered under the banking laws of Pennsylvania, to state nonmember banks of the Federal Reserve, and to banks whose deposits are insured by the FDIC. The subsidiary bank's operations are also subject to regulations of the Pennsylvania Department of Banking and Securities, Federal Reserve, and FDIC.

        The Pennsylvania Department of Banking and Securities, which has primary supervisory authority over banks chartered in Pennsylvania, regularly examines banks in such areas as reserves, loans, investments, management practices, and other aspects of operations. The subsidiary bank is also subject to examination by the FDIC for safety and soundness, as well as consumer compliance. These examinations are designed for the protection of the subsidiary bank's depositors rather than ACNB's shareholders. The subsidiary bank must file quarterly and annual reports to the Federal Financial Institutions Examination Council, or FFIEC.

Monetary and Fiscal Policy

        ACNB and its subsidiary bank are affected by the monetary and fiscal policies of government agencies, including the Federal Reserve and FDIC. Through open market securities transactions and changes in its discount rate and reserve requirements, the Board of Governors of the Federal Reserve exerts considerable influence over the cost and availability of funds for lending and investment. The nature and impact of monetary and fiscal policies on future business and earnings of ACNB cannot be

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predicted at this time. From time to time, various federal and state legislation is proposed that could result in additional regulation of, and restrictions on, the business of ACNB and the subsidiary bank, or otherwise change the business environment. Management cannot predict whether any of this legislation will have a material effect on the business of ACNB.

ACCOUNTING POLICY DISCLOSURE

        Disclosure of the Corporation's significant accounting policies is included in Note A—"Summary of Significant Accounting Policies" in the Notes to Consolidated Financial Statements. Some of these policies are particularly sensitive requiring significant judgments, estimates and assumptions to be made by management. Additional information is contained in Management's Discussion and Analysis for the most sensitive of these issues, including the provision and allowance for loan losses which is located in Note D—"Loans and Allowance for Loan Losses" in the Notes to Consolidated Financial Statements.

        Management, in determining the allowance for loan losses, makes significant judgments. Consideration is given to a variety of factors in establishing this estimate. In estimating the allowance for loan losses, management considers current economic conditions, diversification of the loan portfolio, delinquency statistics, results of internal loan review, financial and managerial strengths of borrowers, adequacy of collateral if collateral dependent or present value of future cash flows, and other relevant factors.

STATISTICAL DISCLOSURES

        The following statistical disclosures are included in Management's Discussion and Analysis, Item 7 hereof, and are incorporated by reference in this Item 1:

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Interest Rate Sensitivity Analysis



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Interest Income and Expense, Volume and Rate Analysis



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Investment Portfolio



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Loan Maturity and Interest Rate Sensitivity



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Loan Portfolio



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Allocation of Allowance for Loan Losses



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Deposits



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Short-Term Borrowings

AVAILABLE INFORMATION

        The Corporation's reports, proxy statements, and other information are available for inspection and copying at the SEC Office of Investor Education and Advocacy at 100 F Street, N.E., Washington, DC 20549, at prescribed rates. The public may obtain information from the Office of Investor Education and Advocacy by calling the Commission at 1-800-SEC-0330. The Corporation is an electronic filer with the Commission. The Commission maintains a website that contains reports, proxy and information statements, and other information regarding registrants that file electronically with the Commission. The address of the Commission's website is https://www.sec.gov.

        Upon a shareholder's written request, a copy of the Corporation's Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K, as required to be filed with the SEC pursuant to Securities Exchange Act Rule 13a-1, may be obtained, without charge, from Lynda L. Glass, Executive Vice President/Secretary & Chief Governance Officer, ACNB Corporation, 16 Lincoln

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Square, P.O. Box 3129, Gettysburg, PA 17325, or visit our website at https://www.acnb.com and click on "Investor Relations".

EMPLOYEES

        As of December 31, 2017, ACNB had 358 full-time equivalent employees. None of these employees are represented by a collective bargaining agreement, and ACNB believes it enjoys good relations with its personnel.

ACQUISITION

        ACNB Corporation and its subsidiaries have experienced stable organic growth. In addition, on July 1, 2017, New Windsor Bancorp, Inc. was acquired as discussed further in this Form 10-K.

ITEM 1A—RISK FACTORS

ACNB IS SUBJECT TO INTEREST RATE RISK.

        ACNB's earnings and cash flows are largely dependent upon its net interest income. Net interest income is the difference between interest income earned on interest-earning assets, such as loans and securities, and interest expense paid on interest-bearing liabilities, such as deposits and borrowed funds. Interest rates are highly sensitive to many factors that are beyond ACNB's control, including general economic conditions and policies of various governmental and regulatory agencies and, in particular, the Board of Governors of the Federal Reserve System. Changes in monetary policy, including changes in interest rates, could influence not only the amount of interest ACNB receives on loans and securities and the amount of interest it pays on deposits and borrowings, but such changes could also affect (i) ACNB's ability to originate loans and obtain deposits, (ii) the fair value of ACNB's financial assets and liabilities, and (iii) the average duration of ACNB's mortgage-backed securities portfolio. If the interest rates paid on deposits and other borrowings increase at a faster rate than the interest rates received on loans and other investments, ACNB's net interest income, and therefore earnings, could be adversely affected. Earnings could also be adversely affected if the interest rates received on loans and other investments fall more quickly than the interest rates paid on deposits and other borrowings.

        Although management believes it has implemented effective asset and liability management strategies to reduce the potential effects of changes in interest rates on ACNB's results of operations, any substantial, unexpected or prolonged change in market interest rates could have a material adverse effect on ACNB's financial condition and results of operations.

ACNB IS SUBJECT TO CREDIT RISK.

        As of December 31, 2017, approximately 56% of ACNB's loan portfolio consisted of commercial and industrial, construction, and commercial real estate loans. These types of loans are generally viewed as having more risk of default than residential real estate loans or consumer loans. These types of loans are also typically larger than residential real estate loans and consumer loans. Because ACNB's loan portfolio contains a significant number of commercial and industrial, construction, and commercial real estate loans with relatively large balances, the deterioration of one or a few of these loans could cause a significant increase in non-performing loans. An increase in non-performing loans could result in a net loss of earnings from these loans, an increase in the provision for loan losses, and an increase in loan charge-offs, all of which could have a material adverse effect on ACNB's financial condition and results of operations.

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ACNB'S ALLOWANCE FOR LOAN LOSSES MAY BE INSUFFICIENT.

        ACNB maintains an allowance for loan losses, which is a reserve established through a provision for loan losses charged to expense, that represents management's best estimate of probable losses that have been incurred within the existing portfolio of loans. The allowance, in the judgment of management, is necessary to reserve for estimated loan losses and risks inherent in the loan portfolio. The level of the allowance reflects management's continuing evaluation of the following: industry concentrations; specific credit risks; loan loss experience; current loan portfolio quality; present economic, political and regulatory conditions; and, unidentified losses inherent in the current loan portfolio. The determination of the appropriate level of the allowance for loan losses inherently involves a high degree of subjectivity and requires ACNB to make significant estimates of current credit risks and future trends, all of which may undergo material changes. Changes in economic conditions affecting borrowers, new information regarding existing loans, identification of additional problem loans, and other factors, both within and outside of ACNB's control, may require an increase in the allowance for loan losses. In addition, bank regulatory agencies periodically review ACNB's allowance for loan losses and may require an increase in the provision for loan losses or the recognition of further loan charge-offs, based on judgments different than those of management. Further, if charge-offs in future periods exceed the allowance for loan losses, ACNB will need additional provisions to increase the allowance for loan losses. Any increases in the allowance for loan losses will result in a decrease in net income, and possibly capital, and may have a material adverse effect on ACNB's financial condition and results of operations.

COMPETITION FROM OTHER FINANCIAL INSTITUTIONS MAY ADVERSELY AFFECT ACNB'S PROFITABILITY.

        ACNB's banking subsidiary faces substantial competition in originating both commercial and consumer loans. This competition comes principally from other banks, credit unions, mortgage banking companies, and other lenders. Many of its competitors enjoy advantages, including greater financial resources with higher lending limits, wider geographic presence, more branch office locations, the ability to offer a wider array of services or more favorable pricing alternatives, and lower origination and operating costs. This competition could reduce the Corporation's net income by decreasing the number and size of loans that its banking subsidiary originates and the interest rates it may charge on these loans.

        In attracting business and consumer deposits, its banking subsidiary faces substantial competition from other insured depository institutions such as banks, savings institutions, and credit unions, as well as institutions offering uninsured investment alternatives, including money market funds. Many of ACNB's competitors enjoy advantages, including greater financial resources, wider geographic presence, more aggressive marketing campaigns, better brand recognition, more branch office locations, the ability to offer a wider array of services or more favorable pricing alternatives, and lower origination and operating costs. These competitors may offer higher interest rates than ACNB, which could decrease the deposits that it attracts or require it to increase its rates to retain existing deposits or attract new deposits. Increased deposit competition could adversely affect the subsidiary's ability to generate the funds necessary for lending operations. As a result, it may need to seek other sources of funds that may be more expensive to obtain and could increase its cost of funds.

        ACNB's banking subsidiary also competes with nonbank providers of financial services, such as brokerage firms, consumer finance companies, credit unions, insurance companies and agencies, and governmental organizations which may offer more favorable terms. Some of its nonbank competitors are not subject to the same extensive regulations that govern ACNB's banking operations. As a result, such nonbank competitors may have advantages over ACNB's banking subsidiary in providing certain products and services. This competition may reduce or limit ACNB's margins on banking services, reduce its market share, and adversely affect its earnings and financial condition.

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THE BASEL III CAPITAL REQUIREMENTS MAY REQUIRE ACNB TO MAINTAIN HIGHER LEVELS OF CAPITAL, WHICH COULD REDUCE ACNB'S PROFITABILITY.

        Basel III targets higher levels of base capital, certain capital buffers, and a migration toward common equity as the key source of regulatory capital. Although the new capital requirements are phased in over future years and may change substantially before final implementation, Basel III signals a growing effort by domestic and international bank regulatory agencies to require financial institutions, including depository institutions, to maintain higher levels of capital. The direction of the Basel III implementation activities or other regulatory viewpoints could require additional capital to support the Corporation's business risk profile prior to final implementation of the Basel III standards. If ACNB and the subsidiary bank are required to maintain higher levels of capital, ACNB and the subsidiary bank may have fewer opportunities to invest capital into interest-earning assets, which could limit the profitable business operations available to ACNB and the subsidiary bank and adversely impact ACNB's financial condition and results of operations.

THE CORPORATION'S OPERATIONS OF ITS BUSINESS, INCLUDING ITS TRANSACTIONS WITH CUSTOMERS, ARE INCREASINGLY DONE VIA ELECTRONIC MEANS, AND THIS HAS INCREASED ITS RISKS RELATED TO CYBERSECURITY.

        The Corporation is exposed to the risk of cyberattacks in the normal course of business. In addition, the Corporation is exposed to cyberattacks on vendors and merchants that affect the Corporation and its customers. In general, cyber incidents can result from deliberate attacks or unintentional events. The Corporation has observed an increased level of attention in the industry focused on cyber-attacks that include, but are not limited to, gaining unauthorized access to digital systems for purposes of misappropriating assets or sensitive information, corrupting data, or causing operational disruption. To combat against these attacks, policies and procedures are in place to prevent or limit the effect of the possible security breach of its information systems. While ACNB maintains insurance coverage that may, subject to policy terms and conditions including significant self-insured deductibles, cover certain aspects of cyber risks, such insurance coverage may be insufficient to cover all losses. While the Corporation has not incurred any material losses related to cyberattacks, nor is it aware of any specific or threatened cyber incidents as of the date of this report, it may incur substantial costs and suffer other negative consequences if it falls victim to successful cyberattacks. Such negative consequences could include remediation costs that may include liability for stolen assets or information and repairing system damage that may have been caused; deploying additional personnel and protection technologies, training employees, and engaging third-party experts and consultants; lost revenues resulting from unauthorized use of proprietary information or the failure to retain or attract customers following an attack; disruption or failures of physical infrastructure, operating systems or networks that support ACNB's business and customers resulting in the loss of customers and business opportunities; additional regulatory scrutiny and possible regulatory penalties; litigation; and, reputational damage adversely affecting customer or investor confidence.

ACNB'S CONTROLS AND PROCEDURES MAY FAIL OR BE CIRCUMVENTED.

        Management regularly reviews and updates ACNB's internal controls, disclosure controls, and procedures, as well as corporate governance policies and procedures. Any system of controls, however well designed and operated, is based in part on certain assumptions and can provide only reasonable, not absolute, assurances that the objectives of the system are met. Any failure or circumvention of ACNB's controls and procedures or failure to comply with regulations related to controls and procedures could have a material adverse effect on ACNB's business, financial condition, and results of operations.

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ACNB'S ABILITY TO PAY DIVIDENDS DEPENDS PRIMARILY ON DIVIDENDS FROM ITS BANKING SUBSIDIARY, WHICH ARE SUBJECT TO REGULATORY LIMITS AND THE BANKING SUBSIDIARY PERFORMANCE.

        ACNB is a financial holding company and its operations are conducted by its subsidiaries. Its ability to pay dividends depends on its receipt of dividends from its subsidiaries. Dividend payments from its banking subsidiary are subject to legal and regulatory limitations, generally based on net profits and retained earnings, imposed by the various banking regulatory agencies. The ability of its subsidiaries to pay dividends is also subject to their profitability, financial condition, capital expenditures, and other cash flow requirements. There is no assurance that its subsidiaries will be able to pay dividends in the future or that ACNB will generate adequate cash flow to pay dividends in the future. ACNB's failure to pay dividends on its common stock could have a material adverse effect on the market price of its common stock.

ACNB'S PROFITABILITY DEPENDS SIGNIFICANTLY ON ECONOMIC CONDITIONS IN THE COMMONWEALTH OF PENNSYLVANIA AND THE STATE OF MARYLAND.

        ACNB's success depends primarily on the general economic conditions of the Commonwealth of Pennsylvania, the State of Maryland, and the specific local markets in which ACNB operates. Unlike larger national or other regional banks that are more geographically diversified, ACNB provides banking and financial services to customers primarily in the southcentral Pennsylvania and northern Maryland region of the country. The local economic conditions in these areas have a significant impact on the demand for ACNB's products and services, as well as the ability of ACNB's customers to repay loans, the value of the collateral securing the loans, and the stability of ACNB's deposit funding sources. A significant decline in general economic conditions caused by inflation, recession, acts of terrorism, outbreak of hostilities or other international or domestic occurrences, unemployment, changes in securities markets, or other factors could impact these local economic conditions and, in turn, have a material adverse effect on ACNB's financial condition and results of operations.

THE EARNINGS OF FINANCIAL SERVICES COMPANIES ARE SIGNIFICANTLY AFFECTED BY GENERAL BUSINESS AND ECONOMIC CONDITIONS.

        ACNB's operations and profitability are impacted by general business and economic conditions in the United States and abroad. These conditions include short-term and long-term interest rates, inflation, money supply, political issues, legislative and regulatory changes, fluctuations in both debt and equity capital markets, broad trends in industry and finance, and the strength of the U.S. economy and the local economies in which ACNB operates, all of which are beyond ACNB's control. Deterioration in economic conditions could result in an increase in loan delinquencies and non-performing assets, decreases in loan collateral values, and a decrease in demand for ACNB's products and services, among other things, any of which could have a material adverse impact on ACNB's financial condition and results of operations.

        The regulatory environment for the financial services industry is being significantly impacted by financial regulatory reform initiatives in the United States and elsewhere, including Dodd-Frank and regulations promulgated to implement it.

        Dodd-Frank, which was signed into law on July 21, 2010, comprehensively reforms the regulation of financial institutions, products and services. Dodd-Frank requires various federal regulatory agencies to implement numerous rules and regulations. Because the federal agencies are granted broad discretion in drafting these rules and regulations, many of the details and the impact of Dodd-Frank may not be known for many months or years.

        While much of how Dodd-Frank and other financial industry reforms will change ACNB's current business operations depends on the specific regulatory reforms and interpretations, many of which have

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yet to be released or finalized, it is clear that the reforms, both under Dodd-Frank and otherwise, will have a significant effect on the entire industry. Although Dodd-Frank and other reforms will affect a number of the areas in which ACNB does business, it is not clear at this time the full extent of the adjustments that will be required and the extent to which ACNB will be able to adjust its businesses in response to the requirements. Although it is difficult to predict the magnitude and extent of these effects at this stage, ACNB believes compliance with Dodd-Frank and implementing its regulations and initiatives will negatively impact revenue and increase the cost of doing business, both in terms of transition expenses and on an ongoing basis, and it may also limit ACNB's ability to pursue certain business opportunities.

NEW LINES OF BUSINESS OR NEW PRODUCTS AND SERVICES MAY SUBJECT ACNB TO ADDITIONAL RISKS.

        From time to time, ACNB may implement new lines of business or offer new products and services within existing lines of business. There are substantial risks and uncertainties associated with these efforts, particularly in instances where the markets are not fully developed. In developing and marketing new lines of business and/or new products and services, ACNB may invest significant time and resources. Initial timetables for the introduction and development of new lines of business and/or new products or services may not be achieved and price and profitability targets may not prove feasible. External factors, such as compliance with regulations, competitive alternatives, and shifting market preferences, may also impact the successful implementation of a new line of business and/or a new product or service. Furthermore, any new line of business and/or new product or service could have a significant impact on the effectiveness of ACNB's system of internal controls. Failure to successfully manage these risks in the development and implementation of new lines of business and new products or services could have a material adverse effect on ACNB's business, financial condition, and results of operations.

ACNB MAY NOT BE ABLE TO ATTRACT AND RETAIN SKILLED PEOPLE.

        ACNB's success depends, in large part, on its ability to attract and retain key people. Competition for the best people in most activities engaged in by ACNB can be intense, and ACNB may not be able to hire people or to retain them. The unexpected loss of services of one or more of ACNB's key personnel could have a material adverse impact on ACNB's business because the Corporation would no longer have the benefit of their skills, knowledge of ACNB's market, as well as years of industry experience, and it would be difficult to promptly find qualified replacement personnel. ACNB and/or one of its subsidiaries currently has employment agreements, including covenants not to compete, with the following named executive officers: its President & Chief Executive Officer; Executive Vice President/Secretary & Chief Governance Officer; Executive Vice President/Treasurer & Chief Financial Officer; the President & Chief Executive Officer of Russell Insurance Group, Inc.; and, the Executive Vice President/Chief Lending & Revenue Officer of ACNB Bank.

ACNB IS SUBJECT TO CLAIMS AND LITIGATION PERTAINING TO FIDUCIARY RESPONSIBILITY.

        From time to time, customers make claims and take legal action pertaining to ACNB's performance of its fiduciary responsibilities. Whether customer claims and legal action related to ACNB's performance of its fiduciary responsibilities are founded or unfounded, if such claims and legal actions are not resolved in a manner favorable to ACNB, they may result in significant financial liability and/or adversely affect the market perception of ACNB and its products and services, as well as impact customer demand for those products and services. Any financial liability or reputation damage could have a material adverse effect on ACNB's business, which, in turn, could have a material adverse effect on ACNB's financial condition and results of operations.

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THE TRADING VOLUME IN ACNB'S COMMON STOCK IS LESS THAN THAT OF OTHER LARGER FINANCIAL SERVICES COMPANIES.

        ACNB's common stock trades on NASDAQ, and the trading volume in its common stock is less than that of other larger financial services companies. A public trading market having the desired characteristics of depth, liquidity and orderliness depends on the presence in the marketplace of willing buyers and sellers of ACNB's common stock at any given time. This presence depends on the individual decisions of investors and general economic and market conditions over which ACNB has no control. Given the lower trading volume of ACNB's common stock, significant sales of ACNB's common stock, and the expectation of these sales, could cause ACNB's stock price to fall.

ACNB OPERATES IN A HIGHLY REGULATED ENVIRONMENT AND MAY BE ADVERSELY AFFECTED BY CHANGES IN FEDERAL, STATE AND LOCAL LAWS AND REGULATIONS.

        ACNB, primarily through its banking subsidiary, is subject to extensive regulation, supervision and/or examination by federal and state banking authorities. Any change in applicable regulations or federal, state or local legislation could have a substantial impact on ACNB and its operations. Additional legislation and regulations that could significantly affect ACNB's powers, authority and operations may be enacted or adopted in the future, which could have a material adverse effect on its financial condition and results of operations. Further, regulators have significant discretion and authority to prevent or remedy unsafe or unsound practices or violations of laws by banks and bank and financial holding companies in the performance of their supervisory and enforcement duties. The exercise of regulatory authority may have a negative impact on ACNB's financial condition and results of operations.

        Like other financial holding companies and financial institutions, ACNB must comply with significant anti-money laundering and anti-terrorism laws. Under these laws, ACNB is required, among other things, to enforce a customer identification program and file currency transaction and suspicious activity reports with the federal government. Government agencies have substantial discretion to impose significant monetary penalties on institutions which fail to comply with these laws or make required reports. While ACNB has policies and procedures designed to prevent any such violations, there can be no assurance that such violations will not occur.

THE SOUNDNESS OF OTHER FINANCIAL INSTITUTIONS MAY ADVERSELY AFFECT ACNB.

        Financial services institutions are interrelated as a result of trading, clearing, counterparty, or other relationships. ACNB has exposure to many different industries and counterparties, and routinely executes transactions with counterparties in the financial services industry, including commercial banks, brokers and dealers, investment banks, and institutional clients. Many of these transactions expose ACNB to credit risk in the event of a default by a counterparty or customer. In addition, ACNB's credit risk may be exacerbated when the collateral held by ACNB cannot be realized upon or is liquidated at prices not sufficient to recover the full amount of the credit exposure due to ACNB. Any such losses could have a material adverse effect on ACNB's financial condition and results of operations.

MARKET VOLATILITY MAY HAVE MATERIALLY ADVERSE EFFECTS ON ACNB'S LIQUIDITY AND FINANCIAL CONDITION.

        The capital and credit markets have experienced extreme volatility and disruption. Over the last several years, in some cases, the markets have exerted downward pressure on stock prices, security prices, and credit capacity for certain issuers without regard to those issuers' underlying financial strength. If the market disruption and volatility returns, there can be no assurance that ACNB will not

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experience adverse effects, which may be material, on its liquidity, financial condition and results of operations.

ACNB MAY NEED OR BE COMPELLED TO RAISE ADDITIONAL CAPITAL IN THE FUTURE WHICH COULD DILUTE SHAREHOLDERS OR BE UNAVAILABLE WHEN NEEDED OR AT UNFAVORABLE TERMS.

        ACNB's regulators or market conditions may require it to increase its capital levels. If ACNB raises capital through the issuance of additional shares of its common stock or other securities, it would likely dilute the ownership interests of current investors and would likely dilute the per share book value and earnings per share of its common stock. Furthermore, it may have an adverse impact on ACNB's stock price. New investors may also have rights, preferences and privileges senior to ACNB's current shareholders, which may adversely impact its current shareholders. ACNB's ability to raise additional capital will depend on conditions in the capital markets at that time, which are outside its control, and on its financial performance. Accordingly, ACNB cannot be assured of its ability to raise additional capital on terms and/or in time frames acceptable to it, or to raise additional capital at all. If ACNB cannot raise additional capital in sufficient amounts when needed, its ability to comply with regulatory capital requirements could be materially impaired. Additionally, the inability to raise capital in sufficient amounts may adversely affect ACNB's operations, financial condition, and results of operations.

ACNB'S FUTURE ACQUISITIONS COULD DILUTE SHAREHOLDER OWNERSHIP AND MAY CAUSE IT TO BECOME MORE SUSCEPTIBLE TO ADVERSE ECONOMIC EVENTS.

        ACNB may use its common stock to acquire other companies or make investments in banks and other complementary businesses in the future. ACNB may also issue additional shares of common stock to pay for future acquisitions, which would dilute current investors' ownership interest in ACNB. Future business acquisitions could be material to ACNB, and the degree of success achieved in acquiring and integrating these businesses into ACNB could have a material effect on the value of ACNB's common stock. In addition, any acquisition could require it to use substantial cash or other liquid assets or to incur debt. In those events, ACNB could become more susceptible to economic downturns and competitive pressures.

PENNSYLVANIA BUSINESS CORPORATION LAW AND VARIOUS ANTI-TAKEOVER PROVISIONS UNDER ACNB'S ARTICLES AND BYLAWS COULD IMPEDE THE TAKEOVER OF ACNB.

        Various Pennsylvania laws affecting business corporations may have the effect of discouraging offers to acquire ACNB, even if the acquisition would be advantageous to shareholders. In addition, ACNB has various anti-takeover measures in place under its articles of incorporation and bylaws, including a supermajority vote requirement for mergers, a staggered Board of Directors, and the absence of cumulative voting. Any one or more of these measures may impede the takeover of ACNB without the approval of the Board of Directors and may prevent shareholders from taking part in a transaction in which they could realize a premium over the current market price of ACNB common stock.

IF ACNB CONCLUDES THAT THE DECLINE IN VALUE OF ANY OF ITS INVESTMENT SECURITIES IS AN OTHER-THAN-TEMPORARY IMPAIRMENT, ACNB IS REQUIRED TO WRITE DOWN THE VALUE OF THAT SECURITY THROUGH A CHARGE TO EARNINGS.

        ACNB reviews its investment securities portfolio at each quarter-end to determine whether the fair value is below the current carrying value. When the fair value of any of its investment securities has declined below its carrying value, ACNB is required to assess whether the decline is an other-than-temporary impairment. If ACNB determines that the decline is an other-than-temporary

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impairment, it is required to write down the value of that security through a charge to earnings for credit related impairment. Non-credit related reductions in the value of a security do not require a write down of the value through earnings unless ACNB intends to, or is required to, sell the security. Changes in the expected cash flows related to the credit related piece of the investment of a security in ACNB's investment portfolio or a prolonged price decline may result in ACNB's conclusion in future periods that an impairment is other than temporary, which would require a charge to earnings to write down the security to fair value. Due to the complexity of the calculations and assumptions used in determining whether an asset has an impairment that is other than temporary, the impairment disclosed may not accurately reflect the actual impairment in the future.

ACNB IS SUBJECT TO POTENTIAL IMPAIRMENT OF GOODWILL AND INTANGIBLES.

        ACNB has certain long-lived assets including purchased intangible assets subject to amortization and associated goodwill assets which are reviewed for impairment annually or whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated undiscounted cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its future cash flows, an impairment charge is recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of would be separately presented in the statement of condition and reported at the lower of the carrying amount or fair value less costs to sell, and are no longer depreciated.

        Goodwill, which has an indefinite useful life, is evaluated pursuant to ASC Topic 350, Intangibles—Goodwill and Other, for impairment annually and is evaluated for impairment more frequently if events and circumstances indicate that the asset might be impaired. An impairment loss is recognized to the extent that the carrying amount exceeds the asset's fair value. The goodwill impairment analysis currently used by the Corporation is a two-step test. The first step, used to identify potential impairment, involves comparing the reporting unit's estimated fair value to its carrying value including goodwill. If the estimated fair value of the reporting unit exceeds its carrying value, goodwill is considered not to be impaired. If the carrying value exceeds estimated fair value, there is an indication of potential impairment and the second step is performed to measure the amount of impairment. If required, the second step involves calculating an implied fair value of goodwill for the reporting unit for which the first step indicated potential impairment. The implied fair value of goodwill is determined in a manner similar to the amount of goodwill calculated in a business combination, by measuring the excess of the estimated fair value of the reporting unit to a group of likely buyers whose cash flow estimates could differ from those of the reporting entity, as determined in the first step, over the aggregate estimated fair values of the individual assets, liabilities and identifiable intangibles as if the reporting unit was being acquired in a business combination. If the implied fair value of goodwill exceeds the carrying value of goodwill assigned to the reporting unit, there is no impairment. If the carrying value of goodwill assigned to the reporting unit exceeds the implied fair value of the goodwill, an impairment charge is recorded for the excess. Subsequent reversal of goodwill impairment losses is not permitted. ACNB performs an annual evaluation to determine if there is goodwill impairment. Further, a new FASB update eliminates the second step test, thus basing impairment on the estimated fair value to the carrying value including goodwill.

ACNB IS SUBJECT TO ENVIRONMENTAL LIABILITY RISK ASSOCIATED WITH LENDING ACTIVITIES.

        A significant portion of ACNB's banking subsidiary loan portfolio is secured by real property. During the ordinary course of business, ACNB may foreclose on and take title to properties securing certain loans. In doing so, there is a risk that hazardous or toxic substances could be found on these properties. If hazardous or toxic substances are found, ACNB may be liable for remediation costs, as

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well as for personal injury and property damage. Environmental laws may require ACNB to incur substantial expense and may materially reduce the affected property's value or limit ACNB's ability to use or sell the affected property. In addition, future laws or more stringent interpretations or enforcement policies with respect to existing laws may increase ACNB's exposure to environmental liability. Although ACNB has policies and procedures to perform an environmental review before initiating any foreclosure action on real property, these reviews may not be sufficient to detect all potential environmental hazards. The remediation costs and any other financial liabilities associated with an environmental hazard could have a material adverse effect on ACNB's financial condition and results of operations.

THE SEVERITY AND DURATION OF A FUTURE ECONOMIC DOWNTURN AND THE COMPOSITION OF THE BANKING SUBSIDIARY'S LOAN PORTFOLIO COULD IMPACT THE LEVEL OF LOAN CHARGE-OFFS AND THE PROVISION FOR LOAN LOSSES AND MAY AFFECT ACNB'S NET INCOME OR LOSS.

        Lending money is a substantial part of ACNB's business through its banking subsidiary. However, every loan that ACNB makes carries a certain risk of non-payment. ACNB cannot assure that its allowance for loan losses will be sufficient to absorb actual loan losses. ACNB also cannot assure that it will not experience significant losses in its loan portfolio that may require significant increases to the allowance for loan losses in the future.

        Although ACNB evaluates every loan that it makes against its underwriting criteria, ACNB may experience losses by reasons of factors beyond its control. Some of these factors include changes in market conditions affecting the value of real estate and unexpected problems affecting the creditworthiness of ACNB's borrowers.

        ACNB determines the adequacy of its allowance for loan losses by considering various factors, including:

•

An analysis of the risk characteristics of various classifications of loans;



•

Previous loan loss experience;



•

Specific loans that would have loan loss potential;



•

Delinquency trends;



•

Estimated fair value of the underlying collateral;



•

Current economic conditions;



•

The views of ACNB's regulators;



•

Reports of internal auditors;



•

Reports of external auditors;



•

Reports of loan reviews conducted by independent organizations; and,



•

Geographic and industry loan concentrations.

        Local economic conditions could impact the loan portfolio of ACNB. For example, an increase in unemployment, a decrease in real estate values, or increases in interest rates, as well as other factors, could weaken the economies of the communities ACNB serves. Weakness in the market areas served by ACNB could depress the Corporation's earnings and, consequently, its financial condition because:

•

Borrowers may not be able to repay their loans;



•

The value of the collateral securing ACNB's loans to borrowers may decline; and/or,



•

The quality of ACNB's loan portfolio may decline.

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        Although, based on the aforementioned procedures implemented by ACNB, management believes the current allowance for loan losses is adequate, ACNB may have to increase its provision for loan losses should local economic conditions deteriorate which could negatively impact its financial condition and results of operations.

CHANGES IN REAL ESTATE VALUES MAY ADVERSELY IMPACT ACNB'S BANKING SUBSIDIARY LOANS THAT ARE SECURED BY REAL ESTATE.

        A significant portion of ACNB's banking subsidiary loan portfolio consists of residential and commercial mortgages, as well as consumer loans, secured by real estate. These properties are concentrated in Adams County, Pennsylvania. Real estate values and real estate markets generally are affected by, among other things, changes in national, regional or local economic conditions, fluctuations in interest rates, the availability of loans to potential purchasers, changes in the tax laws and other government statutes, regulations and policies, and acts of nature. If real estate prices decline, particularly in ACNB's market area, the value of the real estate collateral securing ACNB's loans could be reduced. This reduction in the value of the collateral could increase the number of non-performing loans and could have a material adverse impact on ACNB's financial condition and results of operations.

ACNB'S INFORMATION SYSTEMS MAY EXPERIENCE AN INTERRUPTION OR BREACH IN SECURITY.

        ACNB relies heavily on communications and information systems to conduct its business. Any failure, interruption or breach in security of these systems could result in failures or disruptions in ACNB's customer relationship management, general ledger, deposit, loan and other systems. While ACNB has policies and procedures designed to prevent or limit the effect of the failure, interruption or security breach of its information systems, there can be no assurance that any such failures, interruptions or security breaches will not occur or, if they do occur, that they will be adequately addressed. Although ACNB maintains insurance coverage that may, subject to policy terms and conditions including significant self-insured deductibles, cover certain aspects of cyber risks, such insurance coverage may be insufficient to cover all losses. The occurrence of any failures, interruptions or security breaches of ACNB's information systems could damage ACNB's reputation adversely affecting customer or investor confidence, result in a loss of customer business, subject ACNB to additional regulatory scrutiny and possible regulatory penalties, or expose ACNB to civil litigation and possible financial liability, any of which could have a material adverse effect on ACNB's financial condition and results of operations.

ACNB CONTINUALLY ENCOUNTERS TECHNOLOGICAL CHANGE.

        The financial services industry is continually undergoing rapid technological change with frequent introductions of new technology-driven products and services. The effective use of technology increases efficiency and enables financial institutions to better serve customers and to reduce costs. ACNB's future success depends, in part, upon its ability to address the needs of its customers by using technology to provide products and services that will satisfy customer demands, as well as to create additional efficiencies in ACNB's operations. Many of ACNB's competitors have substantially greater resources to invest in technological improvements. ACNB may not be able to effectively implement new technology-driven products and services or be successful in marketing these products and services to its customers. Failure to successfully keep pace with technological change affecting the financial services industry could have a material adverse impact on ACNB's business and, in turn, ACNB's financial condition and results of operations.

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FINANCIAL SERVICES COMPANIES DEPEND ON THE ACCURACY AND COMPLETENESS OF INFORMATION ABOUT CUSTOMERS AND COUNTERPARTIES.

        In deciding whether to extend credit or enter into other transactions, ACNB may rely on information furnished by or on behalf of customers and counterparties, including financial statements, credit reports, and other financial information. ACNB may also rely on representations of those customers, counterparties or other third parties, such as independent auditors, as to the accuracy and completeness of that information. Reliance on inaccurate or misleading financial statements, credit reports, or other financial information could have a material adverse impact on ACNB's business and, in turn, ACNB's financial condition and results of operations.

CONSUMERS MAY DECIDE NOT TO USE BANKS TO COMPLETE THEIR FINANCIAL TRANSACTIONS.

        Technology and other changes are allowing parties to complete financial transactions that historically have involved banks through alternative methods. For example, consumers can now maintain funds in brokerage accounts or mutual funds that would have historically been held as bank deposits. Consumers can also complete transactions such as paying bills and/or transferring funds directly without the assistance of banks. The process of eliminating banks as intermediaries, known as "disintermediation", could result in the loss of fee income, as well as the loss of customer deposits and the related income generated from those deposits. The loss of these revenue streams and the lower cost deposits as a source of funds could have a material adverse effect on ACNB's financial condition and results of operations.

FUTURE ECONOMIC CONDITIONS MAY ADVERSELY AFFECT SECONDARY SOURCES OF LIQUIDITY.

        In addition to primary sources of liquidity in the form of deposits and principal and interest payments on outstanding loans and investments, ACNB maintains secondary sources that provide it with additional liquidity. These secondary sources include secured and unsecured borrowings from sources such as the Federal Reserve Bank, Federal Home Loan Bank of Pittsburgh, and third-party commercial banks. However, market liquidity conditions have been negatively impacted by past disruptions in the capital markets and could, in the future, have a negative impact on ACNB's secondary sources of liquidity.

SEVERE WEATHER, NATURAL DISASTERS, ACTS OF WAR OR TERRORISM, AND OTHER EXTERNAL EVENTS COULD SIGNIFICANTLY IMPACT ACNB'S BUSINESS.

        The unpredictable nature of events such as severe weather, natural disasters, acts of war or terrorism, and other adverse external events could have a significant impact on ACNB's ability to conduct business. If any of its financial, accounting, network or other information processing systems fail or have other significant shortcomings due to external events, ACNB could be materially adversely affected. Third parties with which ACNB does business could also be sources of operational risk to ACNB, including the risk that the third parties' own network and information processing systems could fail. Any of these occurrences could materially diminish ACNB's ability to operate one or more of the Corporation's businesses, or result in potential liability to customers, reputational damage, and regulatory intervention, any of which could materially adversely affect ACNB. Such events could affect the stability of ACNB's deposit base, impair the ability of borrowers to repay outstanding loans, impair the value of collateral securing loans, impair ACNB's liquidity, cause significant property damage, result in loss of revenue, and/or cause ACNB to incur additional expenses.

        ACNB may be subject to disruptions or failures of the financial, accounting, network and/or other information processing systems arising from events that are wholly or partially beyond ACNB's control,

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which may include, for example, computer viruses, electrical or telecommunications outages, natural disasters, disease pandemics, damage to property or physical assets, or terrorist acts. ACNB has developed a comprehensive business continuity plan which includes plans to maintain or resume operations in the event of an emergency, such as a power outage or disease pandemic, and contingency plans in the event that operations or systems cannot be resumed or restored. The business continuity plan is updated as needed, periodically reviewed, and components are regularly tested. ACNB also reviews and evaluates the business continuity plans of critical third-party service providers. While ACNB believes its business continuity plan and efforts to evaluate the business continuity plans of critical third-party service providers help mitigate risks, disruptions or failures affecting any of these systems may cause interruptions in service to customers, damage to ACNB's reputation, and loss or liability to the Corporation.

CHANGES IN CONTROL OF THE UNITED STATES GOVERNMENT AND ISSUES RELATING TO DEBT AND THE DEFICIT MAY ADVERSELY AFFECT THE CORPORATION.

        The Republican Party controlling of the White House, as well as the Republican Party maintaining or losing control of both the House of Representatives and Senate of the United States in the next congressional election, could result in significant changes or uncertainty in governmental policies, regulatory environments, spending sentiment, and many other factors and conditions, some of which could adversely impact the Corporation's business, financial condition, and results of operations. In addition, as a result of past difficulties of the federal government to reach agreement over federal debt and issues connected with the debt ceiling, certain rating agencies placed the United States government's long-term sovereign debt rating on their equivalent of negative watch and announced the possibility of a rating downgrade. The rating agencies, due to constraints related to the rating of the United States, also placed government-sponsored enterprises in which the Corporation invests and receives lines of credit on negative watch, and a downgrade of the Unites States government's credit rating would trigger a similar downgrade in the credit rating of these government-sponsored enterprises. Furthermore, the credit rating of other entities, such as state and local governments, may also be downgraded should the United States government's credit rating be downgraded. The impact that a credit rating downgrade may have on the national and local economy could have an adverse effect on ACNB's financial condition and results of operations.

ACNB'S BANKING SUBSIDIARY MAY BE REQUIRED TO PAY HIGHER FDIC INSURANCE PREMIUMS OR SPECIAL ASSESSMENTS WHICH MAY ADVERSELY AFFECT ITS EARNINGS.

        Poor economic conditions and the resulting bank failures increased the costs of the FDIC and adversely impacted its Deposit Insurance Fund. Any additional bank failures may prompt the FDIC to increase its premiums or to issue special assessments. ACNB is generally unable to control the amount of premiums or special assessments that its banking subsidiary is required to pay for FDIC insurance. Any future changes in the calculation or assessment of FDIC insurance premiums may have a material adverse effect on ACNB's financial condition and results of operations.

FEDERAL INCOME TAX REFORM COULD HAVE UNFORESEEN EFFECTS ON OUR FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

        On December 22, 2017, the President of the United States signed into law H.R. 1, originally known as the "Tax Cuts and Jobs Act." ACNB is still in the process of analyzing the Tax Cuts and Jobs Act and its possible effects on ACNB. The Tax Cuts and Jobs Act includes a number of provisions, including the lowering of the U.S. corporate tax rate from 35 percent to 21 percent, effective January 1, 2018. There are also provisions that may partially offset the benefit of such rate reduction. Financial statement impacts include adjustments for, among other things, the remeasurement of deferred tax assets and liabilities. While there are benefits, there is also substantial uncertainty regarding the details

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of U.S. Tax Reform. The intended and unintended consequences of the Tax Cuts and Jobs Act on the Corporation's business and on holders of ACNB common shares is uncertain and could be adverse. ACNB anticipates that the impact of the Tax Cuts and Jobs Act may be material to its business, financial condition, and results of operations.

THE INCREASING USE OF SOCIAL MEDIA PLATFORMS PRESENTS NEW RISKS AND CHALLENGES AND THE INABILITY OR FAILURE TO RECOGNIZE, RESPOND TO, AND EFFECTIVELY MANAGE THE ACCELERATED IMPACT OF SOCIAL MEDIA COULD MATERIALLY ADVERSELY IMPACT ACNB'S BUSINESS.

        There has been a marked increase in the use of social media platforms, including weblogs (blogs), social media websites, and other forms of internet-based communications which allow individuals access to a broad audience of consumers and other interested persons. Social media practices in the banking industry are evolving, which creates uncertainty and risk of noncompliance with regulations applicable to ACNB's business. Consumers value readily-available information concerning businesses and their goods and services and often act on such information without further investigation and without regard to its accuracy. Many social media platforms immediately publish the content their subscribers and participants post, often without filters or checks on accuracy of the content posted. Information posted on such platforms at any time may be adverse to ACNB's interests and/or may be inaccurate. The dissemination of information online could harm ACNB's business, prospects, financial condition, and results of operations, regardless of the information's accuracy. The harm may be immediate without affording ACNB an opportunity for redress or correction.

        Other risks associated with the use of social media include improper disclosure of proprietary information, negative comments about ACNB's business, exposure of personally identifiable information, fraud, out-of-date information, and improper use by employees and customers. The inappropriate use of social media by ACNB's employees or customers could result in negative consequences such as remediation costs including training for employees, additional regulatory scrutiny, and possible regulatory penalties, litigation, or negative publicity that could damage ACNB's reputation adversely affecting customer or investor confidence.

A NEW ACCOUNTING STANDARD MAY REQUIRE ACNB TO INCREASE THE ALLOWANCE FOR LOAN LOSSES AND MAY HAVE A MATERIAL ADVERSE EFFECT ON ACNB'S FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

        The Financial Accounting Standards Board has adopted a new accounting standard that will be effective for the Corporation after December 15, 2019. This standard, referred to as Current Expected Credit Loss, or CECL, will require financial institutions to determine periodic estimates of lifetime expected credit losses on loans, and recognize the expected credit losses as allowances for loan losses. This will change the current method of providing allowances for loan losses that are probable, which may require ACNB to increase its allowance for loan losses, and to greatly increase the types of data ACNB would need to collect and review to determine the appropriate level of the allowance for loan losses. Any increase in ACNB's allowance for loan losses or expenses incurred to determine the appropriate level of the allowance for loan losses may have a material adverse effect on ACNB's financial condition and results of operations.

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RISKS RELATING TO THE ACQUISITION OF NEW WINDSOR BANCORP, INC. (NEW WINDSOR) BY ACNB CORPORATION

THE ACQUISITION MAY DISTRACT ACNB'S MANAGEMENT TEAM FROM THEIR OTHER RESPONSIBILITIES.

        Continuing acquisition-related matters could cause the management of ACNB to focus their time and energies on matters related to the acquisition that otherwise would be directed to the Corporation's business and operations. Any such distraction on the part of management, if significant, could affect management's ability to service existing business, develop new business, and adversely affect the combined company's post-acquisition business and earnings.

POST-ACQUISITION INTEGRATION AND CHANGE OF ACNB'S HISTORICAL BUSINESS MODEL MAY FAIL TO ACHIEVE EXPECTED RESULTS.

        The success of the transaction depends heavily on a smooth integration and post-acquisition operations of ACNB. Benefits of the transaction to shareholders may not be realized if the post-acquisition integration is not well executed or well received by each company's historical customers.

ACNB MAY FAIL TO REALIZE THE COST SAVINGS IT EXPECTED TO ACHIEVE FROM THE ACQUISITION.

        The success of the acquisition depends, in part, on ACNB's ability to realize the estimated cost savings from combining the businesses of ACNB and New Windsor. While ACNB believes that the cost savings estimates are achievable, it is possible that the potential cost savings could be more difficult to achieve than ACNB anticipated. ACNB's cost savings estimates also depend on its ability to combine the businesses of ACNB and New Windsor in a manner that permits those cost savings to be realized. If ACNB's estimates are incorrect or it is unable to combine the two successfully, the anticipated cost savings may not be realized fully or at all, or may take longer to realize than expected.

POTENTIAL ACQUISITIONS MAY DISRUPT THE CORPORATION'S BUSINESS AND DILUTE SHAREHOLDER VALUE.

        We regularly evaluate opportunities to acquire and invest in banks and in other complementary businesses. As a result, we may engage in negotiations or discussions that, if they were to result in a transaction, could have a material effect on our operating results and financial condition, including short- and long-term liquidity and capital structure. Our acquisition activities could be material to us. For example, we could issue additional shares of common stock in a purchase transaction, which could dilute current shareholders' ownership interest. These activities could require us to use a substantial amount of cash, other liquid assets, and/or incur debt. In addition, if goodwill recorded in connection with our prior or potential future acquisitions were determined to be impaired, then we would be required to recognize a charge against our earnings, which could materially and adversely affect our results of operations during the period in which the impairment was recognized. Any potential charges for impairment related to goodwill would not impact cash flow, tangible capital or liquidity but would decrease shareholders' equity.

        Our acquisition activities could involve a number of additional risks, including the risks of:

•

incurring time and expense associated with identifying and evaluating potential acquisitions and negotiating potential transactions;



•

using inaccurate estimates and judgments to evaluate credit, operations, management, and market risks with respect to the target institution or its assets;

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•

the time and expense required to integrate the operations and personnel of the combined businesses;



•

creating an adverse short-term effect on our results of operations; and



•

losing key employees and customers as a result of an acquisition that is poorly received.

        We may not be successful in overcoming these risks or any other problems encountered in connection with potential acquisitions. Our inability to overcome these risks could have an adverse effect on our ability to achieve our business strategy and maintain our market value.

RISKS RELATED TO THE WEALTH MANAGEMENT AND INSURANCE INDUSTRIES

REVENUES AND PROFITABILITY FROM OUR WEALTH MANAGEMENT BUSINESS MAY BE ADVERSELY AFFECTED BY ANY REDUCTION IN ASSETS UNDER MANAGEMENT AND SUPERVISION AS A RESULT OF EITHER A DECLINE IN MARKET VALUE OF SUCH ASSETS OR NET OUTFLOWS, WHICH COULD REDUCE TRUST, INVESTMENT ADVISORY AND BROKERAGE AND OTHER SERVINGS FEES EARNED.

        The wealth management business derives the majority of its revenue from noninterest income which consists of trust, investment advisory and brokerage and other servicing fees. Substantial revenues are generated from investment management contracts with clients. Under these contracts, the investment advisory fees paid to us are typically based on the market value of assets under management. Assets under management and supervision may decline for various reasons including declines in the market value of the assets in the funds and accounts managed or supervised, which could be caused by price declines in the securities markets generally or by price declines in specific market segments. Assets under management may also decrease due to redemptions and other withdrawals by clients or termination of contracts. This could be in response to adverse market conditions or in pursuit of other investment opportunities.

THE WEALTH MANAGEMENT INDUSTRY IS SUBJECT TO EXTENSIVE REGULATION, SUPERVISION AND EXAMINATION BY REGULATORS, AND ANY ENFORCEMENT ACTION OR ADVERSE CHANGES IN THE LAWS OR REGULATIONS GOVERNING OUR BUSINESS COULD DECREASE OUR REVENUES AND PROFITABILITY.

        The wealth management business is subject to regulation by a number of regulatory agencies that are charged with safeguarding the integrity of the securities and other financial markets and with protecting the interests of customers participating in those markets. In the event of non-compliance with an applicable regulation, governmental regulators, including the SEC, and FINRA, may institute administrative or judicial proceedings that may result in censure, fines, civil penalties, the issuance of cease-and-desist orders or the deregistration or suspension of the non-compliant broker-dealer or investment adviser or other adverse consequences. The imposition of any such penalties or orders could have a material adverse effect on the wealth management segment's operating results and financial condition. We may be adversely affected as a result of new or revised legislation or regulations. Regulatory changes have imposed and may continue to impose additional costs, which could adversely impact our profitability.

REVENUES AND PROFITABILITY FROM OUR INSURANCE BUSINESS MAY BE ADVERSELY AFFECTED BY MARKET CONDITIONS, WHICH COULD REDUCE INSURANCE COMMISSIONS AND FEES EARNED.

        The revenues of our fee based insurance business are derived primarily from commissions from the sale of insurance policies, which commissions are generally calculated as a percentage of the policy premium. These insurance policy commissions can fluctuate as insurance carriers from time to time

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increase or decrease the premiums on the insurance products we sell. Due to the cyclical nature of the insurance market and the impact of other market and macro economic conditions on insurance premiums, commission levels may vary. The reduction of these commission rates, along with general volatility and/or declines in premiums, may adversely impact our profitability.

ITEM 1B—UNRESOLVED STAFF COMMENTS

        None.

ITEM 2—PROPERTIES

        ACNB Bank, in addition to its main community banking office in Gettysburg, Adams County, Pennsylvania, had a community banking office network of 28 offices in Pennsylvania and Maryland at December 31, 2017. Including the main office, 14 community banking offices are located in Adams County, one is located in Cumberland County, two are located in Franklin County, and five are located in York County, Pennsylvania. There is also a loan production office situated in York County, Pennsylvania. In Maryland, there are seven community banking offices located in Carroll County, all branded as NWSB Bank, a division of ACNB Bank. Bank offices at 19 locations are owned, while 11 are leased. All real estate owned by the subsidiary bank is free and clear of encumbrances. RIG owns an office, free and clear of encumbrances, located in Carroll County, Maryland, and leases an office in Montgomery County, Maryland.

ITEM 3—LEGAL PROCEEDINGS

        As of December 31, 2017, there were no material pending legal proceedings, other than ordinary routine litigation incidental to the business, to which ACNB or its subsidiaries are a party or by which any of their assets are the subject, which could have a material adverse effect on ACNB or its subsidiaries or their results of operations. In addition, no material proceedings are pending or are known to be threatened or contemplated against the Corporation or its subsidiaries by governmental authorities.

ITEM 4—MINE SAFETY DISCLOSURES

        Not Applicable.

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PART II

ITEM 5—MARKET FOR THE REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

        ACNB Corporation's common stock trades on NASDAQ under the symbol ACNB. At December 31, 2017 and 2016, there were 20,000,000 shares of common stock authorized, 7,086,258 and 6,126,738 shares issued, respectively, and 7,023,658 and 6,064,138 shares outstanding, respectively. As of December 31, 2017, ACNB had approximately 2,341 stockholders of record. At December 31, 2017 and 2016, there were 62,600 shares of treasury stock purchased by the Corporation through the common stock repurchase program approved in October 2008. There have been no shares purchased during the most recent quarter and 57,400 shares can still be purchased under the program. ACNB is restricted as to the amount of dividends that it can pay to stockholders by virtue of the restrictions on the banking subsidiary's ability to pay dividends to ACNB under the Pennsylvania Banking Code, the Federal Deposit Insurance Corporation Act, and the regulations of the FDIC. For further information, please refer to Note J—"Regulatory Restrictions on Dividends" and Note N—"Regulatory Matters" in the Notes to Consolidated Financial Statements.

        On May 5, 2009, stockholders approved and ratified the ACNB Corporation 2009 Restricted Stock Plan, effective as of February 24, 2009, in which awards shall not exceed, in the aggregate, 200,000 shares of common stock. As of December 31, 2017, there were 19,301 shares of common stock granted as restricted stock awards to employees of the subsidiary bank. The maximum number of shares that may yet be granted under the restricted stock plan is 180,699. The Corporation's Registration Statement under the Securities Act of 1933 on Form S-8 for the ACNB Corporation 2009 Restricted Stock Plan was filed with the Securities and Exchange Commission on January 4, 2013.

        On May 5, 2009, stockholders approved and adopted the amendment to the Articles of Incorporation of ACNB Corporation to authorize up to 20,000,000 shares of preferred stock, par value $2.50 per share. As of December 31, 2017, there were no issued or outstanding shares of preferred stock.

        On January 24, 2011, the ACNB Corporation Dividend Reinvestment and Stock Purchase Plan was introduced for stockholders of record. This plan provides registered holders of ACNB Corporation common stock with a convenient way to purchase additional shares of common stock by permitting participants in the plan to automatically reinvest cash dividends on all or a portion of the shares owned and to make quarterly voluntary cash payments under the terms of the plan. Participation in the plan is voluntary, and there are eligibility requirements to participate in the plan. As of December 31, 2017, there were 137,654 shares of common stock issued through the ACNB Corporation Dividend Reinvestment and Stock Purchase Plan.

        There have been no unregistered sales of stock in 2017, 2016 or 2015.

        The following table reflects the quarterly high and low prices of ACNB's common stock and the cash dividends on the common stock for the periods indicated.

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        The Corporation used the Mid-Atlantic Custom Peer Group—Asset $700M-$2B performance graph below, which management believes better represents the Corporation's performance versus other financial institutions of similar size.

Total Return Performance

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ITEM 6—SELECTED FINANCIAL DATA

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ITEM 7—MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

INTRODUCTION

        The following is management's discussion and analysis of the significant changes in the financial condition, results of operations, comprehensive income, capital resources, and liquidity presented in its accompanying consolidated financial statements for ACNB Corporation (the Corporation or ACNB), a financial holding company. Please read this discussion in conjunction with the consolidated financial statements and disclosures included herein. Current performance does not guarantee, assure or indicate similar performance in the future.

CRITICAL ACCOUNTING POLICIES

        The accounting policies that the Corporation's management deems to be most important to the portrayal of its financial condition and results of operations, and that require management's most difficult, subjective or complex judgment, often result in the need to make estimates about the effect of such matters which are inherently uncertain. The following policies are deemed to be critical accounting policies by management:

        The allowance for loan losses represents management's estimate of probable losses inherent in the loan portfolio. Management makes numerous assumptions, estimates and adjustments in determining an adequate allowance. The Corporation assesses the level of potential loss associated with its loan portfolio and provides for that exposure through an allowance for loan losses. The allowance is established through a provision for loan losses charged to earnings. The allowance is an estimate of the losses inherent in the loan portfolio as of the end of each reporting period. The Corporation assesses the adequacy of its allowance on a quarterly basis. The specific methodologies applied on a consistent basis are discussed in greater detail under the caption, Allowance for Loan Losses, in a subsequent section of this Management's Discussion and Analysis of Financial Condition and Results of Operations.

        The evaluation of securities for other-than-temporary impairment requires a significant amount of judgment. In estimating other-than-temporary impairment losses, management considers various factors including the length of time the fair value has been below cost, the financial condition of the issuer, and the Corporation's intent to sell, or requirement to sell, the security before recovery of its value. Declines in fair value that are determined to be other than temporary are charged against earnings.

        Accounting Standards Codification (ASC) Topic 350, Intangibles—Goodwill and Other, requires that goodwill is not amortized to expense, but rather that it be assessed or tested for impairment at least annually. Impairment write-downs are charged to results of operations in the period in which the impairment is determined. The Corporation did not identify any impairment on RIG's outstanding goodwill from its most recent testing, which was performed as of October 1, 2017. If certain events occur which might indicate goodwill has been impaired, the goodwill is tested for impairment when such events occur. The Corporation has not identified any such events, and, accordingly, has not tested goodwill resulting from the acquisition of New Windsor Bancorp, Inc. (New Windsor) for impairment during the year ended December 31, 2017. ACNB plans on testing New Windsor goodwill during 2018. Other acquired intangible assets with finite lives, such as customer lists, are required to be amortized over the estimated lives. These intangibles are generally amortized using the straight line method over estimated useful lives of ten years.

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EXECUTIVE OVERVIEW

        On July 1, 2017, ACNB Corporation acquired New Windsor Bancorp, Inc. (New Windsor) and New Windsor State Bank. The acquisition was part of ACNB Corporation's long-term strategic plan to enhance shareholder value by systematically and methodically expanding into new geographic markets and growing our customer base. Nonrecurring expenses normally associated with the acquisition amounted to $3.0 million net of the corresponding tax impact at the marginal tax rate. The acquisition added to top line revenue and, after giving effect to the nonrecurring merger-related expenses accounted for under GAAP, the acquisition positively impacted and accreted to the Corporation's bottom line and earnings per share. A second nonrecurring event that caused 2017 additional expense, but will produce a subsequent immediate positive net income effect, was federal tax legislation known as the Tax Cuts and Jobs Act (the "Tax Act"). The Tax Act made broad and complex changes to the U.S. tax code, including a reduction in the base federal corporate tax rate from the prior existing statutory rate, which was 35% for ACNB Corporation, to 21%. As with most Banking companies, the Tax Act resulted in a one-time, noncash charge against 2017 net income of approximately $1.7 million for the Corporation, due to the write-down of the Corporation's net deferred tax assets.

        ACNB Corporation uses non-GAAP financial measures to provide information useful to investors in understanding our operating performance and trends, and to facilitate comparisons with the performance of our peers. The non-GAAP financial measures and key performance indicators we use may differ from the non-GAAP financial measures and key performance indicators other financial institutions use to measure their performance and trends. Reconciliations of GAAP to non-GAAP operating measures to the most directly comparable GAAP financial measures are included in the tables below.

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        This non-GAAP 2017 net income figure of $14,498,000 represents a 29.8% increase over the comparable results for the year ended December 31, 2016. Basic earnings per share on the 2017 non-GAAP measures increased 20.0% over the non-GAAP earnings per share for 2016.

        The primary source of the Corporation's revenues is net interest income derived from interest earned on loans and investments, less deposit and borrowing funding costs. Revenues are influenced by general economic factors, including market interest rates, the economy of the markets served, stock market conditions, as well as competitive forces within the markets.

        The Corporation's overall strategy is to increase loan growth in local markets, while maintaining a reasonable funding base by offering competitive deposit products and services. The year 2017 continued to be challenging for financial institutions with new expensive compliance regulations, slowly recovering housing markets, lingering wage stagnation, and slow uneven growth. ACNB continued to be profitable and well capitalized despite the legacy effects of the United States economy's recent past.

        In alignment with the Corporation's strategic plan for long-term geographic expansion, ACNB acquired New Windsor Bancorp, Inc. of Taneytown, Maryland, and its subsidiary bank, New Windsor State Bank. Banking operations in the new south region include seven community banking offices located in Carroll County, Maryland, and branded as NWSB Bank, a division of ACNB Bank. The operating results of this new division are included with ACNB's other operations as of July 1, 2017. Before and after the acquisition, ACNB incurred $4,728,000 and $472,000 in merger-related expenses for the years ended December 31, 2017 and 2016, respectively. Higher net interest income and improved fee income offset increased expenses resulting in increased income before income taxes of $16,422,000 in 2017, compared to $14,637,000 and $14,778,000 in 2016 and 2015, respectively. In addition, the Tax Cuts and Jobs Act resulted in a charge against 2017 net income of approximately $1,700,000 due to the write-down of net deferred tax assets. This one-time charge along with the recurring income tax expense decreased net income to $9,788,000, or $1.50 per share, in 2017, compared to $10,869,000, or $1.80 per share, in 2016 and $11,017,000, or $1.83 per share, in 2015. Returns on average equity were 7.12%, 9.17% and 9.77% in 2017, 2016 and 2015, respectively.

        In 2017, the Corporation's net interest margin increased to 3.51%, compared to 3.35% and 3.45% in 2016 and 2015, respectively. Net interest income was $46,352,000 in 2017, as compared to $36,566,000 in 2016 and $35,606,000 in 2015.

        Other income was $14,149,000, $13,208,000 and $12,406,000 in 2017, 2016 and 2015, respectively. The largest source of other income is commissions from insurance sales attributable to Russell Insurance Group, Inc. (RIG). Commissions from insurance sales increased by 4.2% in 2017 to $5,024,000, boosted by higher personal lines insurance volume and contingent commissions as a result of specific actions of the insurance carriers. In 2017, no gain was recognized on sold investments. In 2016, a $26,000 gain was recognized on sold or merged investments compared to a gain of $261,000 in 2015. In 2016, a $449,000 gain was recognized on the sale of a bank office building, which was sold in order to gain better efficiencies. Income from fiduciary, investment management and brokerage activities totaled $2,012,000 for 2017, as compared to $1,684,000 for 2016 and $1,589,000 for 2015. This income increased from new account relationships and increased market values in accounts. Service charges on deposit accounts increased 24.1% to $2,940,000 for 2017 due to the business combination as of July 1, 2017, as well as concerted management of this fee source; while revenue from ATM and debit card transactions increased 17.5% to $1,762,000 due to increased combined customer volume.

        Other expenses increased to $44,079,000, or by 25.4%, in 2017, as compared to $35,137,000 in 2016. Other expenses totaled $33,234,000 in 2015. The largest component of other expenses is salaries and employee benefits, which increased 11.1% to $24,654,000 in 2017, compared to $22,200,000 in 2016, due to an increase in combined organization employees, annual merit increases, and the increased cost of benefits despite lower pension expense. Compared to 2016, occupancy expense increased 16.3% in 2017 due to the seven new community banking office locations in Maryland and

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normal repair and maintenance variations, and equipment expense rose 23.3% from maintenance of technology assets. Professional services expense increased 33.1% from increasing risk, loan, legal and corporate governance engagements. Marketing and corporate relations expense decreased by 24.6% due to less specific campaigns and brand awareness activities. FDIC and regulatory expense increased by 5.4% based on these agencies' formulas. In 2017, foreclosed real estate expenses increased $38,000, or 69.1%, resulting from variation in carrying cost. Merger-related expenses were $4,728,000 in 2017, compared to $472,000 in 2016, as the acquisition of New Windsor was finalized in 2017. A more thorough discussion of the Corporation's results of operations is included in the following pages.

RESULTS OF OPERATIONS

Net Interest Income

        The primary source of ACNB's traditional banking revenue is net interest income, which represents the difference between interest income on earning assets and interest expense on liabilities used to fund those assets. Earning assets include loans, securities, and interest bearing deposits with banks. Interest bearing liabilities include deposits and borrowings.

        Net interest income is affected by changes in interest rates, volume of interest bearing assets and liabilities, and the composition of those assets and liabilities. The "interest rate spread" and "net interest margin" are two common statistics related to changes in net interest income. The interest rate spread represents the difference between the yields earned on interest earning assets and the rates paid for interest bearing liabilities. The net interest margin is defined as the percentage of net interest income to average earning assets, which also considers the Corporation's net non-interest bearing funding sources, the largest of which are non-interest bearing demand deposits and stockholders' equity.

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        The following table includes average balances, rates, interest income and expense, interest rate spread, and net interest margin:

Table 1—Average Balances, Rates and Interest Income and Expense

        For yield calculation purposes, nonaccruing loans are included in average loan balances. Loan fees (expense) of $(48,000), $11,000 and $(172,000) as of December 31, 2017, 2016 and 2015, respectively, are included in interest income. Yields on tax-exempt securities and loans are not tax effected.

        Table 1 presents balance sheet items on a daily average basis, net interest income, interest rate spread, and net interest margin for the years ending December 31, 2017, 2016 and 2015. Table 2 analyzes the relative impact on net interest income for changes in the volume of interest earning assets

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and interest bearing liabilities and changes in rates earned and paid by the Corporation on such assets and liabilities.

        Net interest income totaled $46,352,000 in 2017, as compared to $36,566,000 in 2016 and $35,606,000 in 2015. During 2017, net interest income increased from higher loan volume (including acquired loans) in the earning asset mix and positive rate variances in earning assets from the acquired loans and from purchase accounting adjustments. Funding costs increased from higher volume (including acquired funding) and from higher rates paid. The increase in net interest income in 2016 was due to increases in loan volume in the earning asset mix offset by negative rate variances in earning assets and funding costs.

        The net interest margin during 2017 was 3.51% compared to 3.35% during 2016. The margin increased as a result of purchased accounting adjustments which added 11 basis point to the margin, and acquiring and originating loans at the current market rate in order to increase loan volume and attempt to maintain total net interest income net of purchasing lower yielding investments to properly collateralize local government accounts and repurchase agreements. The Federal Open Market Committee repeatedly decreased the federal funds rate from September 2007 to December 2008 and had maintained it at 0% to 0.25% until mid-December 2015 when this rate was increased in stages to its current range of 1.25% to 1.50%. In addition, the Federal Reserve Bank embarked on various programs referred to as Quantitative Easing which, in effect, attempted to lower rates on longer term portions of the yield curve. These decreases allowed interest rate reductions on lower-cost transactional deposit products and higher-cost certificates of deposit (CD's) over the intervening years; however, economic progress allowed the Federal Reserve to end new Quantitative Easing and to signal rates they control would eventually increase. ACNB took steps to ameliorate the effect of rising rates including promoting longer term CD's however interest in low cost transaction accounts increased; the result was a 0.07% increase in funding costs in 2017. In addition to the slightly higher cost of funds in 2017, earning asset yields continued up, increasing 0.22% from purchase accounting adjustments and a higher mix of lending. The decreased earning asset yields in 2016 were 0.11% compared to funding cost declines of 0.01%. Maintaining the net interest margin going forward will be challenged by the fact that substantial amounts of deposits rates are increasing, while loans rate increases are restrained due to competition. The cost and availability of wholesale funding could also be affected by a variety of internal and external factors resulting from interest rate market factors and the creditworthiness of the Corporation and the credit providers.

        Average earning assets were $1,318,741,000 in 2017, an increase of 20.9% from the balance of $1,090,326,000 in 2016, which was an increase from $1,031,924,000 in 2015. Loan growth and the $263,450,000 New Windsor loans acquired, represented the largest increase in average assets in 2017, 2016 and 2015, in conjunction with changes in the investment portfolio in those years to balance liquidity needs and to collateralize eligible deposits. Average interest bearing liabilities were $1,041,466,000 in 2017, up from $874,565,000 in 2016 and up from $842,458,000 in 2015. Average non-interest bearing demand deposits increased 30.2% in 2017, continuing the upward trend from 2016 and 2015. This increase in deposits was attributed to $283,333,000 of relationships from the New Windsor acquisition and the value placed on stability and FDIC insurance by depositors. On average, deposits (including non-interest bearing) were up 22.4%, while borrowings increased by 9.0% due to acquired subordinated debt in the New Windsor acquisition. Lower-cost transaction and savings deposits increased in 2017 as a result of the New Windsor acquisition. The increase in time deposit was a result of the New Windsor acquisition and an effort to retain funding by offering higher time deposit rates. Lower time deposits from prior years was attributed to depositors dissatisfied by the Federal Reserve induced low rate environment and perhaps investing in equity markets.

        The rate/volume analysis detailed in Table 2 shows that the increase in net interest income in 2017 was due to loan volume increases and rate increases in earning asset offsetting rate and volume increases in funding cost. Earning asset yields increased due to New Windsor acquired assets, purchase accounting adjustments and market rate increases. Interest expense increased due to higher deposit volumes and rates and the acquired subordinated debt.

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        The following table shows changes in net interest income attributed to changes in rates and changes in average balances of interest earning assets and interest bearing liabilities:

Table 2—Rate/Volume Analysis

        The net change attributable to the combination of rate and volume has been allocated on a consistent basis between volume and rate based on the absolute value of each. For yield calculation purposes, nonaccruing loans are included in average balances.

Provision for Loan Losses

        The provision for loan losses charged against earnings was $0 in 2017, 2016 and 2015. The determination of no need for additional provision was a result of the analysis of the adequacy of the allowance for loan losses calculation. The allowance for loan and lease losses does not include the loans acquired from the New Windsor acquisition which were recorded at fair value as of the acquisition date. Each quarter, the Corporation assesses risk in the loan portfolio compared with the balance in the allowance for loan losses and the current evaluation factors. Management concluded that the loan portfolio exhibited continued general improvement in quantitative and qualitative measurements as shown in the tables and narrative in this Management's Discussion and Analysis and the Notes to the Consolidated Financial Statements. This assessment concluded that credit quality was stable, charge offs were low and past due loans manageable. This same analysis concluded that the unallocated allowance was appropriate.

        For additional discussion of the provision and the loans associated therewith, please refer to the Asset Quality section of this Management's Discussion and Analysis. ACNB charges confirmed loan losses to the allowance and credits the allowance for recoveries of previous loan charge-offs. For 2017, the Corporation had net charge-offs of $218,000 as compared to net charge-offs of $553,000 for 2016.

Other Income

        Other income was $14,149,000 for the year ended December 31, 2017, a $941,000, or 7.1%, increase from 2016. Other income was $13,208,000 for the year ended December 31, 2016, an $802,000,

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or 6.5%, increase from 2015. The largest source of other income is commissions from insurance sales from RIG, which increased 4.2% to $5,024,000 in 2017, and increased 4.1% to $4,822,000 in 2016. The increases were due to higher contingent commission payments and an increase in personal lines commission income. The contingent, or extra, commissions is at the discretion of various insurance carriers in accordance with applicable insurance regulations. Heightened pressure on commissions is expected to continue in this business line.

        In 2017, no gain was recognized on sold or merged securities compared to a gain of $26,000 in 2016, and a gain of $261,000 in 2015. Securities were sold in 2015 to balance state and local geographic mix. In addition, an equity position recognized a $158,000 gain from a merger transaction in 2015 and an additional $26,000 in 2016 when the position was liquidated. Income from fiduciary, investment management and brokerage activities, which includes fees from both institutional and personal trust, investment management services, estate settlement and brokerage services, totaled $2,012,000 for the year ended December 31, 2017, as compared to $1,684,000 for 2016 and $1,589,000 for 2015. At December 31, 2017, ACNB had total assets under administration of approximately $327,000,000, compared to $195,000,000 at the end of 2016 and $178,000,000 at the end of 2015. $103,000,000 in brokerage relationships were brought over in the New Windsor acquisition. The variations in income were in part due to more assets under management and higher estate settlement income which varies with specific activity.

        Service charges on deposit accounts increased 24.1% to $2,940,000, after increasing 2.6% in 2016, due to the acquired New Windsor deposit base and based upon varying customer actions that affect the volume of fees. Further, certain government regulations and policies effective since 2010 limited service charge increases and make future revenue levels uncertain. Revenue from ATM and debit card transactions increased 17.5% to $1,762,000 due to higher volume including the acquired New Windsor deposit base. The longer term trend of increased fees resulted from consumer desire to use more electronic delivery channels; however, regulations or legal challenges for large financial institutions may impact industry pricing for such transactions and fees in connection therewith in future periods, the effect of which cannot be currently quantified. Another threat to this revenue source is the security breaches in the merchant base that are negatively affecting consumer confidence in the debit card channel. Income from sold mortgages, included in other income, decreased by $156,000, or 23.6%, to $505,000 in 2017 as customer demand moved to mortgage types that cannot be sold in the secondary market and must be retained in portfolio. This revenue source is subject to wide divergence due to national and local economic trends. 2016 experienced a $449,000 gain on the sale of a bank administrative office building in order to gain better efficiencies.

Impairment Testing

        RIG has certain long-lived assets, including purchased intangible assets subject to amortization such as insurance books of business, and associated goodwill assets, which are reviewed for impairment annually or whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated undiscounted cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its future cash flows, an impairment charge is recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of would be separately presented in the statement of condition and reported at the lower of the carrying amount or fair value less costs to sell, and are no longer depreciated.

        Goodwill, which has an indefinite useful life, is evaluated for impairment annually and is evaluated for impairment more frequently if events and circumstances indicate that the asset might be impaired. An impairment loss is recognized to the extent that the carrying amount exceeds the asset's fair value. Accounting rules permit an entity to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. The goodwill

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impairment analysis currently used by the Corporation is a two-step test. The first step, used to identify potential impairment, involves comparing the reporting unit's estimated fair value to its carrying value, including goodwill. If the estimated fair value of the reporting unit exceeds its carrying value, goodwill is considered not to be impaired. If the carrying value exceeds the estimated fair value, there is an indication of potential impairment and the second step is performed to measure the amount of impairment. If required, the second step involves calculating an implied fair value of goodwill for the reporting unit for which the first step indicated potential impairment. The implied fair value of goodwill is determined in a manner similar to the amount of goodwill calculated in a business combination, by measuring the excess of the estimated fair value of the reporting unit to a group of likely buyers whose cash flow estimates could differ from those of the reporting entity, as determined in the first step, over the aggregate estimated fair values of the individual assets, liabilities and identifiable intangibles as if the reporting unit was being acquired in a business combination. If the implied fair value of goodwill exceeds the carrying value of goodwill assigned to the reporting unit, there is no impairment. If the carrying value of goodwill assigned to the reporting unit exceeds the implied fair value of the goodwill, an impairment charge is recorded for the excess. Subsequent reversal of goodwill impairment losses is not permitted. Further, a new FASB update eliminates the second step test, thus basing impairment on the estimated fair value to the carrying value including goodwill.

        As noted above, commissions from insurance sales were up 4.2% in 2017, and RIG's stand alone net income increased 3.4% in 2017 compared to 2016 (exclusive of income from deferred tax liability revaluing in conjunction with the Tax Act). The testing for potential impairment involves methods that include both current and projected income amounts, and RIG's fair value remained above the carrying value as of the most recent annual impairment test date. Thus, the results of the annual evaluations determined that there was no impairment of RIG's goodwill, including the testing at October 1, 2017. However, declines in RIG's net income or changes in external market factors, including likely buyers that are assumed in impairment testing, may require an impairment charge to goodwill. The Corporation has not identified any such events, and, accordingly, has not tested goodwill resulting from the acquisition of New Windsor for impairment during the year ended December 31, 2017. ACNB plans on testing New Windsor goodwill during 2018. Should it be determined in a future period that the goodwill has been impaired, then a charge to earnings will be recorded in the period that such a determination is made.

Other Expenses

        Other expenses increased 25.4% to $44,079,000 for the year ended December 31, 2017. The largest component of other expenses is salaries and employee benefits, which increased 11.1% in 2017 to $24,654,000 compared to $22,200,000 in 2016, and increased $1,268,000, or 6.1%, from 2015 to 2016. The reasons for the increase in salaries and employee benefits expenses include the following:

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retaining customer-facing staff in the NWSB Bank markets to retain key loan and deposit relationships;



•

increased staff in support functions and higher skilled mix of employees necessitated by regulations and growth;



•

normal merit increases to employees and associated payroll taxes;



•

higher performance-based commissions and incentives;



•

higher employee benefit plan costs, including health insurance;



•

increases related to 401(k) plan and non-qualified retirement plan benefits; and,



•

decreased defined benefit pension expense due to plan investment performance and changes in discount rates (decreasing the liabilities for future obligations).

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        The Corporation reduced the benefit formula for the defined benefit pension plan effective January 1, 2010, in order to manage total benefit costs. Subsequently, the Corporation amended the defined benefit pension plan effective April 1, 2012, in that no employee hired after March 31, 2012, shall be eligible to participate in the pension plan and no inactive or former plan participant shall be eligible to again participate in the pension plan. The Corporation's overall pension plan investment strategy is to achieve a mix of investments to meet the long-term rate of return assumption and near-term pension obligations with a diversification of asset types, fund strategies, and fund managers. The mix of investments is adjusted periodically by retaining an advisory firm to recommend appropriate allocations after reviewing the Corporation's risk tolerance on contribution levels, funded status, plan expense, as well as any applicable regulatory requirements. However, the determination of future benefit expense is also dependent on the fair value of assets and the discount rate on the year-end measurement date, which in recent years has experienced fair value volatility and low discount rates. The expense will be lower in 2018 due to the improved plan return in 2017 and changes in discount rates. A pension provision in a public law known as MAP-21, enacted in July 2012, had no effect on reducing the GAAP expense associated with the plan. In addition, the ACNB plan has maintained a well-funded status under ERISA rules.

        Net occupancy expense was up 16.3% at $2,403,000 in 2017, $2,066,000 in 2016, and $2,170,000 in 2015. Equipment expense totaled $3,757,000 during 2017, as compared to $3,046,000 during 2016 and $3,007,000 during 2015. Occupancy expense was up in 2017 mostly due to seven more offices from the New Windsor acquisition and equipment expense increased in 2017 due to ongoing support and maintenance of financial systems applications and security technology. Equipment expense is subject to ever-increasing technology demands and the need for system upgrades for security and reliability purposes.

        Professional services expense totaled $1,134,000 for 2017, as compared to $852,000 for 2016 and $844,000 for 2015. The variation in expense from year to year included varying legal costs associated with problem loans and corporate governance, as well as the expense of heightened compliance monitoring on existing regulations and the expense of implementing new regulations including the Dodd-Frank Act. Other tax expense increased $6,000 or 0.8% in 2017 compared to 2016 due to a rate increase mostly offset by recoveries on sales tax challenges, and increased from 2015 to 2016 due to increased net equity base. The 2018 expense will increase due to the addition of the equity increase from the New Windsor acquisition. Supplies and postage expense increased in 2017 compared to the prior year due to new offices and postage for the customer base of the NWSB Bank division. 2016 also increased from 2015 due to growth.

        Marketing and corporate relations expense decreased 24.6% from 2016 to 2017, and increased 27.0% from 2015 to 2016. Marketing expense varies with the timing and amount of planned advertising production and media expenditures, typically related to the promotion of certain in-market banking and trust products.

        FDIC and regulatory expense for 2017 was $644,000, an increase of $33,000 from $611,000 in 2016. FDIC and regulatory expense in 2015 was $665,000. FDIC expense varies with changes in net asset size, risk ratings, and FDIC derived assessment rates.

        Foreclosed assets held for resale consist of the fair value of real estate acquired through foreclosure on real estate loan collateral or the acceptance of ownership of real estate in lieu of the foreclosure process. Fair values are based on appraisals that consider the sales prices of similar properties in the proximate vicinity less estimated selling costs. Foreclosed real estate expenses were $93,000, $55,000 and $119,000 for the years ended December 31, 2017, 2016 and 2015, respectively. Expenses increased in 2017 due to high carrying cost (maintenance, taxes, etc.) of the few properties held. The higher expense in 2015 was a result of properties that suffered decreases in value after acquisition (requiring write-downs to fair value) during the prolonged marketing cycles for these

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distressed properties and, in some cases, during which the debtor remained in physical possession while eviction actions were contested and finally executed. Values are written down based upon updated appraisals less selling costs (which in the often extended marketing periods can create multiple year expenses) and other fair value adjustments, or in some cases properties are written down based on sales agreements that do not subsequently close. In all, the historically high costs of all years consisted of these write-downs and other costs to carry and was due to the increased number and varying mix of commercial and residential collateral for which such carrying costs include insurance, property maintenance, unpaid and ongoing property taxes, and deferred maintenance required upon acquisition. Foreclosed real estate expenses will vary in 2018 depending on the successful sales on some existing properties and the unknown expenses related to new properties acquired.

        Intangible assets amortization increased 55.7% from the core deposit intangible in the New Windsor acquisition and to a lesser extent from small insurance books purchased. Other operating expense increased $689,000 or 19.8% in 2017 as a result of a variety of increases including various data channels, corporate governance and risk management (including training) expenditures. Other operating expense increased 5.9% in 2016 from 2015 as a result of a variety of variances in the same categories.

        Acquisition and integration costs related to the New Windsor acquisition totaled $4,728,000 in 2017 compared to $472,000 in 2016. Merger expenses included legal and consulting expenses to effect the legal merger, investment banking and preparing purchase accounting adjustments. Integration expenses included certain severance payments to New Windsor staff separated by the merger, consultant costs to integrate New Windsor bank systems into ACNB's, and the cost to terminate all New Windsor core banking and electronic technology systems contracts. These costs were all necessary to provide requisite internal controls and cost effective core banking technology systems going forward. The costs of integrating all systems into one system was important to the acquisition viability and ongoing system integrity and quality.

Provision for Income Taxes

        ACNB recognized income taxes of $6,634,000, or 40.4% of pretax income, during 2017, as compared to $3,768,000, or 25.7%, during 2016 and $3,761,000, or 25.5%, during 2015. The variances from the federal statutory rate are generally due to tax-exempt income from investments in and loans to state and local units of government at below-market rates (an indirect form of taxation), investment in bank-owned life insurance, and investments in low-income housing partnerships (which qualify for federal tax credits).

        On December 22, 2017, the United States government enacted comprehensive tax legislation, known as the Tax Cuts and Jobs Act (the "Tax Act"). The Tax Act made broad and complex changes to the U.S. tax code, including a reduction in the base corporate tax rate from the prior existing statutory rate, which was 35% for ACNB, to 21%. Based on estimates and current accounting guidance, the Corporation estimated that the Tax Act resulted in a charge against 2017 net income of approximately $1.7 million, due to the write down of ACNB's net deferred tax assets due to the Tax Act's reduction in the base corporate tax rate to 21%. This estimate was based on a review and analysis of the Corporation's net deferred tax assets at December 31, 2017, as well as adjustments to various deferred tax assets and deferred tax liabilities in the fourth quarter, including those accounted for in accumulated other comprehensive income.

        Otherwise, the increasing effective tax rate during 2017, 2016, and 2015 was a result of increasing pretax income in relationship to expiration of tax credits and lower levels of tax-exempt investments. Pretax income increased due to internal growth and the New Windsor acquisition. At December 31, 2017, net deferred tax assets amounted to $2,739,000. Deferred tax assets are realizable primarily through future reversal of existing taxable temporary differences and future earnings. Management

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currently anticipates timing difference reversals will be adequate to utilize deferred tax assets. Accordingly, no valuation allowance has been established for deferred tax assets at December 31, 2017.

FINANCIAL CONDITION

        Average earning assets increased in 2017 to $1,318,741,000, or by 20.9%, from $1,090,326,000 in 2016 following $1,031,924,000 in 2015. ACNB's overnight interest bearing deposits decreased in 2017 on average, as more funds were allocated into investments. On average, investments increased in 2017 and 2016 to properly collateralize public deposits. Average loans increased 25.9% and 6.2% on average in 2017 and 2016, respectively. Besides $263,450,000 in loans acquired from New Windsor, growth in loans was funded by increased deposits, investment cash flow and term FHLB borrowings. Average deposits increased 22.4% in 2017 to $1,146,311,000 from $936,190,000 in 2016 and $877,448,000 in 2015. Deposit growth was the result of the New Windsor acquisition. Average borrowings increased in 2017 to $126,958,000 from $116,459,000 in 2016 and $118,670,000 in 2015. Fluctuations in borrowings are term borrowing to fund loan demand and variations in local customer repurchase accounts, which are akin to deposits.

Investment Securities

        ACNB uses investment securities to generate interest and dividend income, manage interest rate risk, provide collateral for certain funding products, and provide liquidity. The changes in the securities portfolio in 2017 were mainly to provide proper collateral for public deposits. Investing into investment security portfolio assets over the last several years was made more challenging due to the Federal Reserve Bank's program commonly called Quantitative Easing in which, by the Federal Reserve's open market purchases, the yields were maintained at a lower level than would otherwise be the case. Fair value of $21,264,000 was acquired through the New Windsor acquisition. These securities were similar to the portfolio mix of ACNB. The investment portfolio is comprised of U.S. Government agency, municipal, and corporate securities. These securities provide the appropriate characteristics with respect to credit quality, yield and maturity relative to the management of the overall balance sheet.

        At December 31, 2017, the securities balance included a net unrealized loss on available for sale securities of $957,000, net of taxes, on amortized cost of $160,290,000 versus a net unrealized loss of $266,000, net of taxes, on amortized cost of $143,393,000 at December 31, 2016. The change in fair value of available for sale securities during 2017 was a result of the securities acquired from New Windsor and the higher amount of investments in the available for sale portfolio, offset in part by a decrease in fair value from an increase in the U.S. Treasury yield curve rates and the spread from this yield curve required by investors on the types of investment securities that ACNB owns. The Federal Reserve ceased their rate-decreasing Quantitative Easing program in 2014 and increased the fed funds rate in mid-December 2015 through 2017, along with an U.S. presidential election result that, at least to date, has caused the U. S. Treasury yield curve to increase in the time terms relevant to the investment securities in the Corporation's portfolio. Previously, after a prolonged period of inaction by the Federal Reserve after lowering rates on the yield curve most conducive to stimulating the housing market and to boost employment and consumption was augmented by a combination of weak domestic and international economic conditions, leading to generally lower rates on the yield curve. However, fair values were volatile on any given day in 2017 and such volatility will continue.

        At December 31, 2017, the securities balance included held to maturity securities with an amortized cost of $44,829,000 and a fair value of $44,549,000, as compared to an amortized cost of $55,568,000 and a fair value of $55,425,000 at December 31, 2016. The held to maturity securities are U.S. government agency debentures and pass-through mortgage-backed securities in which the full payment of principal and interest is guaranteed; however, they were not classified as available for sale because these securities are generally used as required collateral for certain eligible government accounts or repurchase agreements. They are also held for possible pledging to access additional liquidity for banking subsidiary needs in the form of FHLB borrowings. No held to maturity securities were acquired from New Windsor.

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        The Corporation does not own investments consisting of pools of Alt-A or subprime mortgages, private label mortgage-backed securities, or trust preferred investments.

        The fair values of securities available for sale (carried at fair value) are determined by obtaining quoted market prices on nationally recognized securities exchanges (Level 1) or by matrix pricing (Level 2), which is a mathematical technique used widely in the industry to value debt securities without relying exclusively on quoted market prices for the specific security but rather by relying on the security's relationship to other benchmark quoted prices. The Corporation uses independent service providers to provide matrix pricing. Please refer to Note C—"Securities" in the Notes to Consolidated Financial Statements for more information on the security portfolio and Note L—"Fair Value Measurements" in the Notes to Consolidated Financial Statements for more information about fair value.

        The following tables set forth the composition of the securities portfolio and the securities maturity schedule, including weighted average yield, as of the end of the years indicated:

Table 3—Investment Securities

        Table 4 discloses investment securities at the scheduled maturity date at December 31, 2017. Many securities have call features that make their redemption possible before the stated maturity date.

Table 4—Securities Maturity Schedule

        Securities are at amortized cost. Mortgage-backed securities are allocated based upon scheduled maturities.

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Loans

        Year over year, loans outstanding increased by $336,260,000, or 37.0%, in 2017, as compared to 6.4% growth experienced in 2016; the increase in 2017 was primarily from the fair value acquired from New Windsor of $263,450,000 and the balance was a net increase of new loans net of payoff and paydowns. Both years demonstrated the determined efforts by management to lend to creditworthy borrowers subject to the Corporation's disciplined underwriting standards, despite the generally slow economic conditions and intense competition. The higher percentage increase in 2017 was largely due to the increase in loan value from the New Windsor acquisition. Within the portfolio, higher growth was centered in increased commercial purpose loans/commercial construction loans, while lower growth was in local market residential mortgages. The commercial purpose segments increased $219,553,000, or 46.3%, during 2017, spread among diverse categories that include farmland secured, loans to local government units, and other types of commercial lending. Residential real estate mortgage lending, which includes smaller commercial purpose loans secured by the owner's home, increased by $115,074,000, or 27.5%, to local borrowers who preferred loan types that would not be sold into the secondary mortgage market. Included in the mortgage increase were $44,205,000 in residential mortgage loans secured by junior liens or home equity loans, which are also in many cases junior liens. Junior liens inherently have more credit risk by virtue of the fact that another financial institution may have a senior security position in the case of foreclosure liquidation of collateral to extinguish the debt. Generally, foreclosure actions could become more prevalent if the real estate market weakens, property values deteriorate, or rates increase sharply. Included in commercial purpose were real estate construction loans up $20,289,000, or 132.9% in 2017, as a result of some stabilization in the residential real estate market despite stricter underwriting on this loan type due to the category's credit attributes.

        A similar higher mix of commercial purpose loans was included in the $54,950,000 or 6.4% increase in 2016 compared to 2015 as the result of efforts in commercial real estate lending as residential mortgages were mostly sold.

        Included in the commercial, financial and agricultural category are loans to Pennsylvania school districts, municipalities (including townships) and essential purpose authorities. In most cases, these loans are backed by the general obligation of the local government body. In many cases, these loans are obtained through a bid process with other local and regional banks. The loans are bank qualified for mostly tax-free interest income treatment for federal income taxes. These loans totaled $88,484,000 in 2017, an increase of 20.8% over $73,242,000 held at the end of 2016. The amount outstanding at the end of 2015 was $59,948,000, an increase of $12,595,000 over 2014.

Table 5—Loan Portfolio

        Loans at December 31 were as follows:

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        The repricing range of the loan portfolio at December 31, 2017, and the amounts of loans with predetermined and fixed rates are presented in the tables below:

Table 6—Loan Sensitivities

LOANS MATURING

LOANS BY REPRICING OPPORTUNITY

        Most of the Corporation's lending activities are with customers located within southcentral Pennsylvania and in the northern Maryland area. This region currently and historically has lower unemployment than the U.S. as a whole. Included in commercial real estate loans are loans made to lessors of non-residential properties that total $269,080,000, or 21.6% of total loans, at December 31, 2017. These borrowers are geographically dispersed throughout ACNB's marketplace and are leasing commercial properties to a varied group of tenants including medical offices, retail space, and other commercial purpose facilities. Because of the varied nature of the tenants, in aggregate, management believes that these loans present an acceptable risk when compared to commercial loans in general. ACNB does not originate or hold Alt-A or subprime mortgages in its loan portfolio.

Asset Quality

        The ACNB loan portfolio is subject to varying degrees of credit risk. Credit risk is mitigated through prudent underwriting standards, ongoing credit review, and monitoring and reporting asset quality measures. Additionally, loan portfolio diversification, limiting exposure to a single industry or borrower, and requiring collateral also reduces ACNB's credit risk.

        ACNB's commercial, consumer and residential mortgage loans are principally to borrowers in southcentral Pennsylvania and northern Maryland. As the majority of ACNB's loans are located in this area, a substantial portion of the debtor's ability to honor the obligation may be affected by the level of economic activity in the market area.

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        The unemployment rate in ACNB's market area remained below the state and national average during 2017. Additionally, low interest rates, a less volatile local economy, and minimal inflation continued to provide some support to the economic conditions in the area. During 2017, continued low activity in new residential real estate development/construction and general lower economic activity lingered from the 2007 to 2009 major recession, challenging the Corporation's marketplace commercial activity. Slower growth areas such as ACNB's marketplace generally do not retract in economic recessions as quickly and as low as other areas of the country, however the recovery from low economic cycles are also generally slower.

        Non-performing assets include nonaccrual loans and restructured loans (troubled debt restructures or TDRs), accruing loans past due 90 days or more, and other foreclosed assets. The accrual of interest on residential mortgage and commercial loans (consisting of commercial and industrial, commercial real estate, and commercial real estate construction loan categories) is discontinued at the time the loan is 90 days past due unless the credit is well secured and in the process of collection. Consumer loans (consisting of home equity lines of credit and consumer loan categories) are typically charged off no later than 120 days past due. Past due status is based on contractual terms of the loan. In all cases, loans are placed on nonaccrual or charged off at an earlier date if collection of principal or interest is considered doubtful. ACNB occasionally returns nonaccrual loans to performing status when the borrower brings the loan current and performs in accordance with contractual terms for a reasonable period of time. ACNB categorizes a loan as a TDR if it changes the terms of the loan, such as interest rate, repayment schedule or both, to terms that it otherwise would not have granted to a borrower, for economic or legal reasons related to the borrower's financial difficulties.

        The following table sets forth the Corporation's non-performing assets as of the end of the years indicated:

Table 7—Non-Performing Assets

        If interest due on all nonaccrual loans had been accrued at original contract rates, it is estimated that income before income taxes would have been greater by $437,000 in 2017, $369,000 in 2016, and $456,000 in 2015. The increase in nonaccrual loans from 2016 to 2017 is discussed further below.

        Impaired loans at December 31, 2017 and 2016, totaled $10,337,000 and $11,945,000, respectively. At December 31, 2017 and 2016, $3,405,000 and $377,000, respectively, of the impaired loans were troubled debt restructured loans, which were also classified as nonaccrual. $3,982,000 and $7,443,000 of the impaired loans were accruing troubled debt restructured loans at December 31, 2017 and 2016, respectively. Loans whose terms are modified are classified as troubled debt restructurings if the borrowers have been granted concessions and it is deemed that those borrowers are experiencing

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financial difficulty. Concessions granted under a troubled debt restructuring generally involve interest rates being granted below current market rates for the credit risk of the loan or an extension of a loan's stated maturity date. Nonaccrual troubled debt restructurings are restored to accrual status if principal and interest payments, under the modified terms, are current for six consecutive months after modification. Loans classified as troubled debt restructurings are designated as impaired. The related allowance for loan losses on impaired loans totaled $1,229,000 and $932,000 at December 31, 2017 and 2016, respectively. The decrease in accruing troubled debt restructurings was due to a retreat property that was moved to nonaccrual status in 2017 when continued payments were in doubt. The increase in nonaccrual loans was related to the retreat property and smaller credits net of payments received. Potential problem loans are defined as performing loans that have characteristics that cause management to have doubts as to the ability of the borrower to perform under present loan repayment terms and which may result in the reporting of these loans as non-performing loans in the future. Total additional potential problem loans approximated $1,064,000 at December 31, 2017, compared to $2,768,000 at December 31, 2016.

        Foreclosed assets held for resale consists of the fair value of real estate acquired through foreclosure on real estate loan collateral or the acceptance of ownership of such real estate in lieu of the foreclosure process. Fair values are based on appraisals that consider the sale prices of similar properties in the proximate vicinity less estimated selling costs. Foreclosed assets held for resale totaled $436,000 at December 31, 2017. One construction real estate property was brought into foreclosed real estate in 2015 with an aggregate fair value of $63,000. In addition, the fair value of $373,000 for foreclosed real estate at December 31, 2017, represented one business and two residential real estate single family homes, which were taken into foreclosed real estate in 2017. All properties are being actively marketed to targeted buyers by external and internal resources. The total of $256,000 in foreclosed real estate at December 31, 2016, represented one construction real estate property, and three single family homes.

Allowance for Loan Losses

        ACNB maintains the allowance for loan losses at a level believed to be adequate by management to absorb probable losses in the loan portfolio, and it is funded through a provision for loan losses charged to earnings. On a quarterly basis, ACNB utilizes a defined methodology in determining the adequacy of the allowance for loan losses, which considers specific credit reviews, past loan losses, historical experience, and qualitative factors. This methodology results in an allowance that is considered appropriate in light of the high degree of judgment required and that is prudent and conservative, but not excessive.

        Management assigns internal risk ratings for each commercial lending relationship. Utilizing historical loss experience, adjusted for changes in trends, conditions and other relevant factors, management derives estimated losses for non-rated and non-classified loans. When management identifies impaired loans with uncertain collectibility of principal and interest, it evaluates a specific reserve on a quarterly basis in order to estimate potential losses. Management's analysis considers:

•

adverse situations that may affect the borrower's ability to repay;



•

the current estimated fair value of underlying collateral; and,



•

prevailing market conditions.

        If management determines a loan is not impaired, a specific reserve allocation is not required. Management then places the loan in a pool of loans with similar risk factors and assigns the general loss factor to determine the reserve. For homogeneous loan types, such as consumer and residential mortgage loans, management bases specific allocations on the average loss ratio for the previous three

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years for each specific loan pool. Additionally, management adjusts projected loss ratios for other factors, including the following:

•

lending policies and procedures, including underwriting standards and collection, charge-off, and recovery practices;



•

national, regional, and local economic and business conditions, as well as the condition of various market segments, including the impact on the value of underlying collateral for collateral dependent loans;



•

nature and volume of the portfolio and terms of loans;



•

experience, ability and depth of lending management and staff;



•

volume and severity of past due, classified and nonaccrual loans, as well as other loan modifications; and,



•

existence and effect of any concentrations of credit and changes in the level of such concentrations.

        Management determines the unallocated portion of the allowance for loan losses, which represents the difference between the reported allowance for loan losses and the calculated allowance for loan losses, based on the following criteria:

•

risk of imprecision in the specific and general reserve allocations;



•

the perceived level of consumer and small business loans with demonstrated weaknesses for which it is not practicable to develop specific allocations;



•

other potential exposure in the loan portfolio;



•

variances in management's assessment of national, regional, and local economic conditions; and,



•

other internal or external factors that management believes appropriate at that time.

        The unallocated portion of the allowance is deemed to be appropriate as it reflects an uncertainty that remains in the loan portfolio; specifically reserves where the Corporation believes that tertiary losses are probable above the loss amount derived using appraisal-based loss estimation, where such additional loss estimates are in accordance with regulatory and GAAP guidance. Appraisal-based loss derivation does not fully develop the loss present in certain unique, ultimately bank-owned collateral. The Corporation has determined that the amount of provision in 2017 and the resulting allowance at December 31, 2017, are appropriate given the continuing level of risk in the loan portfolio. Further, management believes the unallocated allowance is appropriate, because even though the impaired loans added since 2016 demonstrate generally low risk due to adequate real estate collateral, the value of such collateral can decrease; plus, the growth in the loan portfolio is centered around commercial real estate which continues to have little increase in value and low liquidity. In addition, there are certain loans that, although they did not meet the criteria for impairment, management believes there was a strong possibility that these loans represented potential losses at December 31, 2017. The amount of unallocated decreased at December 31, 2017 as management concluded that the loan portfolio exhibited continued general improvement in quantitative and qualitative measurements. This assessment concluded that credit quality was stable, charge offs were low and past due loans manageable.

        Management believes the above methodology accurately reflects losses inherent in the portfolio. Management charges actual loan losses to the allowance for loan losses. Management periodically updates the methodology and the assumptions discussed above.

        Management bases the provision for loan losses, or lack of provision, on the overall analysis taking into account the methodology discussed above, which is consistent with recent improvement in the

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credit quality in the loan portfolio. The provision for 2017 was $0, or the same as the provision for 2016 and 2015. The decrease in the allowance for loan losses to total loans of 1.56% at December 31, 2016 to 1.12% at December 31, 2017, is primarily related to the acquisition of New Windsor loans at fair value with no allowance for loan losses accordingly at the acquisition date.

        Federal and state regulatory agencies, as an integral part of their examination process, periodically review the Corporation's allowance for loan losses and may require the Corporation to recognize additions to the allowance based on their judgments about information available to them at the time of their examination, which may not be currently available to management. Based on management's comprehensive analysis of the loan portfolio and economic conditions, management believes the current level of the allowance for loan losses is adequate.

        The following tables set forth information on the analysis of the allowance for loan losses and the allocation of the allowance for loan losses as of the dates indicated:

Table 8—Analysis of Allowance for Loan Losses

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Table 9—Allocation of the Allowance for Loan Losses

        The allowance for loan losses at December 31, 2017, was $13,976,000, or 1.12% of loans, as compared to $14,194,000, or 1.56% of loans, at December 31, 2016. The ratio of non-performing loans plus foreclosed assets to total assets was 0.52% at December 31, 2017, as compared to 0.51% at December 31, 2016.

        Loans past due 90 days and still accruing were $1,507,000 and nonaccrual loans were $6,355,000 as of December 31, 2017. Loans past due 90 days and still accruing were $1,345,000 at December 31, 2016, while nonaccruals were $4,502,000.

        Additional information on nonaccrual loans at December 31, 2017 and 2016, is as follows:

        All nonaccrual impaired loans are to borrowers located within the market area served by the Corporation in southcentral Pennsylvania and nearby areas of northern Maryland. All nonaccrual impaired loans were originated by ACNB's banking subsidiary, except for one participation loan discussed below, between 1995 and 2015 for purposes listed in the classifications in the table above.

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        Included in commercial real estate construction at December 31, 2017, the Corporation had no impaired and nonaccrual loans. On another loan previously in this category, foreclosure was held in abeyance while allowing the pursuit of a workout plan. The workout plan resulted in payment of the impaired nonaccrual balance concluding in the second quarter of 2016.

        Owner occupied commercial real estate and construction includes nine unrelated loan relationships, all of which, except for a $2,256,000 loan relationship for a retreat property, have balances of less than $833,000 each, for which the real estate is collateral and is used in connection with a business enterprise that is suffering economic stress or is out of business. The retreat property loan originated in 2008 was added to nonaccrual in the second quarter of 2017 and is current with modified terms and is supported by adequate collateral. One of two improved parcels is being actively marketed for sale. Another property added in the second quarter of 2017 is an $832,000 loan with modified terms and conditions originated in 2011 secured by a tourism related lodging real estate that was assigned $60,000 in specific allocation based on sales contract. The property was sold subsequent to year end at a smaller loss. A third property added in the second quarter of 2017 is a $597,000 loan relationship ($444,000 in commercial and industrial and $153,000 in owner occupied commercial real estate) with normal terms and conditions secured by a construction business assets that was assigned $247,000 in specific allocation based on bankruptcy filings. All assets including real estate are being liquidated with bankruptcy court supervision. The other loans in this category were originated between 1995 and 2012 and are business loans impacted by specific borrower credit situations. Most loans in this category are making principal payments. Collection efforts will continue unless it is deemed in the best interest of the Corporation to initiate foreclosure procedures. One loan was removed in 2017 after the borrower established an extended period of regular payments.

        Investment/rental residential real estate includes two loan relationships totaling $478,000 for which the real estate is collateral and the purpose of which is for speculation, rental, or other non-owner occupied uses. One $377,000 loan with multiple separate rental houses was added in the second quarter of 2016 and has a $377,000 specific loss allocation based on a current appraisal adjusted for partial sales. One unrelated loan for approximately $100,000, in this category at April 2015, was stayed from further foreclosure action by a bankruptcy filing.

        Included in impaired commercial and industrial loans is a participation loan with standard terms and conditions including repayment from conversion of trade assets for a business in southcentral Pennsylvania in Chapter 11 bankruptcy that has a balance of $188,000, which is net of $1,528,000 in principal payments since it was moved to nonaccrual in the third quarter of 2014 after becoming delinquent. Liquidation of trade assets is in process. Besides trade assets, the loan is fully guaranteed by a government sponsored entity so no specific allocation was deemed to be necessary. An unrelated $868,000 commercial loan relationship to finance a subcontract and change orders was moved to nonaccrual in the fourth quarter of 2016 with a $517,000 specific allocation when part of the amount due to the subcontractor to perform on the loan was in dispute with the contractor and continues to be litigated.

        The Corporation utilizes a systematic review of its loan portfolio on a quarterly basis in order to determine the adequacy of the allowance for loan losses. In addition, ACNB engages the services of an outside independent loan review function and sets the timing and coverage of loan reviews during the year. The results of this independent loan review are included in the systematic review of the loan portfolio. The allowance for loan losses consists of a component for individual loan impairment, primarily based on the loan's collateral fair value and expected cash flow. A watch list of loans is identified for evaluation based on internal and external loan grading and reviews. Loans other than those determined to be impaired are grouped into pools of loans with similar credit risk characteristics. These loans are evaluated as groups with allocations made to the allowance based on historical loss experience adjusted for current trends in delinquencies, trends in underwriting and oversight, concentrations of credit, and general economic conditions within the Corporation's trading area. The

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provision expense was based on the loans discussed above, as well as current trends in the watch list and the local economy as a whole. The charge-offs discussed elsewhere in this Management's Discussion and Analysis create the recent loss history experience and result in the qualitative adjustment which, in turn, affects the calculation of losses inherent in the portfolio. The lack of provision for loan losses for 2017, 2016, and 2015, was a result of the measurement of the adequacy of the allowance for loan losses at each period. The acquisition of New Windsor loans at fair value did not require a provision expense. More specifically, with the manageable level of nonaccrual loans and with substandard loans decreasing in 2017, no provision addition to the allowance was necessary in proportion to nonaccrual and substandard loans in accordance with management's belief that adequate collateralization generally exists for these loans in accordance with GAAP. Each quarter, the Corporation assesses risk in the loan portfolio compared with the balance in the allowance for loan losses and the current evaluation factors.

Premises and Equipment

        During the quarter ended June 30, 2016, a building was sold and the Corporation is leasing back a portion of that building. In connection with these transactions, a gain of $1,147,000 was realized, of which $447,000 was recognized in the quarter ended June 30, 2016 and the remaining $700,000 deferred for future recognition over the lease back term. A reduction of lease expense of $70,000 was recognized in 2017. A reduction of lease expense of $32,000 was recognized in 2016. ACNB valued six buildings acquired from New Windsor at $8,624,000 at July 1, 2017.

Foreclosed Assets Held for Resale

        The carrying value of real estate acquired through foreclosure was $436,000 at December 31, 2017, compared to $256,000 at December 31, 2016. The increase was mainly due to three properties that were added in 2017, two of which were acquired from New Windsor at fair value. One additional unrelated commercial property for $63,000 was added in 2015. All properties are actively being marketed. The Corporation expects to obtain and market additional foreclosed assets in 2018; however, the total amount and timing is currently not certain.

Other Assets

        Other assets increased $3,718,000, or 18.6%, in 2017 compared to 2016, in part due to the New Windsor acquisition.

Deposits

        ACNB relies on deposits as the primary source of funds for lending activities. Average deposits increased 22.4%, or $210,121,000, during 2017, as compared to a 6.7% increase during 2016. Deposits acquired from New Windsor totaled $293,333,000 on July 1, 2017. ACNB's deposit pricing function employs a disciplined pricing approach based upon alternative funding rates, but also strives to price deposits to be competitive with relevant local competition, including a local government investment trust, credit unions and larger regional banks. The 2017 average deposit increase in part was due to a shift to transaction accounts as customers put more value in liquidity and FDIC insurance. Products, such as money market accounts and interest-bearing transaction accounts that had suffered declines in past years, continued with recovered balances; however, more recent trends suggest a return to more normal, lower balances. Year-end 2016 to year-end 2017 recorded an increase in deposits of $330,871,000, or 34.2%, which was in large part deposits acquired from New Windsor. With persistent low market interest rates in a slow economy, ACNB's ability to maintain and add to its deposit base may be impacted by the reluctance of consumers to accept low rates and by competition willing to pay above market rates to attract market share. Alternatively, if rates rise rapidly and the equity markets recover, funds could leave the Corporation or be priced higher to maintain deposits.

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Table 10—Time Deposits

        Maturities of time deposits of $100,000 or more outstanding at December 31, 2017, are summarized as follows:

Borrowings

        Short-term borrowings are comprised primarily of securities sold under agreements to repurchase and short-term borrowings from the FHLB. As of December 31, 2017, short-term borrowings were $36,908,000, an increase of $2,318,000, or 6.7%, from the December 31, 2016, balance of $34,590,000. Agreements to repurchase accounts are within the commercial and local government customer base and have attributes similar to core deposits. Investment securities are pledged in sufficient amounts to collateralize these agreements. Compared to year-end 2016, repurchase agreement balances were up due to fluctuations in the business activities of ACNB's commercial and local government customer base. At December 31, 2017, there were $0 in short-term FHLB borrowings, due to daily fluctuation in deposits and loans. Long-term borrowings consist of longer-term advances from the FHLB that provides term funding of loan assets, and Corporate borrowings that were acquired or originated in regards to the acquisition of New Windsor. Long-term borrowings totaled $94,600,000 at December 31, 2017, versus $74,250,000 at December 31, 2016. The Corporation increased long-term borrowings 27.4% from December 31, 2016. A $4.6 million borrowing from a local bank was made to fund cash payment to shareholders of the New Windsor acquisition. $10.8 million was added to FHLB borrowings to fund balance loan demand in excess of deposit growth. Laddered FHLB fixed-rate term advances were taken in 2017 to mature from 2019 to 2021 to reduce net liability sensitivity. In addition, $5 million was subordinated debt acquired from New Windsor. Further borrowings will be used when necessary for a variety of risk management and funding purposes. Please refer to the Liquidity discussion below for more information on the Corporation's ability to borrow.

        The following tables set forth information about the Corporation's short-term borrowings as of the dates indicated:

 

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Capital

        ACNB's capital management strategies have been developed to provide an appropriate rate of return, in the opinion of management, to stockholders, while maintaining its "well capitalized" regulatory position in relationship to its risk exposure. Total stockholders' equity was $153,966,000 at December 31, 2017, compared to $120,061,000 at December 31, 2016. Stockholders' equity increased during 2017, a net result of earnings retained in capital during 2017, and new shares issued as a result of the New Windsor acquisition. The acquisition of New Windsor resulted in 938,360 new ACNB shares issued to the New Windsor shareholders valued at $28,620,000.

        A $115,000 decrease in accumulated other comprehensive loss was a result of a net increase in the fair value of the investment portfolio and changes in the net funded position of the defined benefit pension plan. Other comprehensive income or loss is mainly caused by fixed-rate investment securities gaining or losing value in different interest rate environments and changes in the net funded position of the defined benefit pension plan.

        The primary source of additional capital to ACNB is earnings retention, which represents net income less dividends declared. During 2017, ACNB retained $4,555,000, or 46.5%, of its net income, as compared to $6,029,000, or 55.5%, in 2016 and $6,197,000, or 56.2%, in 2015.

        ACNB Corporation has a Dividend Reinvestment and Stock Purchase Plan that provides registered holders of ACNB Corporation common stock with a convenient way to purchase additional shares of common stock by permitting participants in the plan to automatically reinvest cash dividends on all or a portion of the shares owned and to make quarterly voluntary cash payments under the terms of the plan. Participation in the plan is voluntary, and there are eligibility requirements to participate in the plan. Cumulative to December 31, 2017, 137,654 shares were issued under this plan with proceeds in the amount of $2,679,000 since its inception in 2011. Proceeds are used for general corporate purposes.

        ACNB Corporation has a Restricted Stock plan available to selected officers and employees of the Bank, to advance the best interest of ACNB Corporation and its shareholders. The plan provides those persons who have responsibility for its growth with additional incentive by allowing them to acquire an ownership in ACNB Corporation and thereby encouraging them to contribute to the success of the Corporation. To date, 19,301 shares were issued under this plan. Proceeds are used for general corporate purposes.

        ACNB is subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on ACNB. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, ACNB must meet specific capital guidelines that involve quantitative measures of its assets, liabilities, and certain off-balance sheet items as calculated under regulatory accounting practices. The capital amounts and reclassifications are also subject to qualitative judgments by the regulators about components, risk weightings, and other factors.

        Quantitative measures established by regulation to ensure capital adequacy require ACNB to maintain minimum amounts and ratios of total and Tier 1 capital to average assets. Management believes, as of December 31, 2017 and 2016, that ACNB's banking subsidiary met all minimum capital adequacy requirements to which it is subject and is categorized as "well capitalized" for regulatory purposes. There are no subsequent conditions or events that management believes have changed the banking subsidiary's category.

Regulatory Capital Changes

        In July 2013, the federal banking agencies issued final rules to implement the Basel III regulatory capital reforms and changes required by the Dodd-Frank Act. The phase-in period for community

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banking organizations began January 1, 2015, while larger institutions (generally those with assets of $250 billion or more) began compliance effective January 1, 2014. The final rules call for the following capital requirements:

•

a minimum ratio of common Tier 1 capital to risk-weighted assets of 4.5%;



•

a minimum ratio of Tier 1 capital to risk-weighted assets of 6.0%;



•

a minimum ratio of total capital to risk-weighted assets of 8.0%; and,



•

a minimum leverage ratio of 4.0%.

        In addition, the final rules establish a common equity Tier 1 capital conservation buffer of 2.5% of risk-weighted assets applicable to all banking organizations. If a banking organization fails to hold capital above the minimum capital ratios and the capital conservation buffer, it will be subject to certain restrictions on capital distributions and discretionary bonus payments. The phase-in period for the capital conservation and countercyclical capital buffers for all banking organizations began on January 1, 2016.

        Under the initially proposed rules, accumulated other comprehensive income (AOCI) would have been included in a banking organization's common equity Tier 1 capital. The final rules allow community banks to make a one-time election not to include these additional components of AOCI in regulatory capital and instead use the existing treatment under the general risk-based capital rules that excludes most AOCI components from regulatory capital. The opt-out election must be made in the first call report or FR Y-9 series report that is filed after the financial institution becomes subject to the final rule. The Corporation elected to opt-out.

        The rules permanently grandfather non-qualifying capital instruments (such as trust preferred securities and cumulative perpetual preferred stock) issued before May 19, 2010, for inclusion in the Tier 1 capital of banking organizations with total consolidated assets of less than $15 billion as of December 31, 2009, and banking organizations that were mutual holding companies as of May 19, 2010. ACNB Corporation does not have trust preferred securities or cumulative perpetual preferred stock with no plans to add these to the capital structure.

        The proposed rules would have modified the risk-weight framework applicable to residential mortgage exposures to require banking organizations to divide residential mortgage exposures into two categories in order to determine the applicable risk weight. In response to commenter concerns about the burden of calculating the risk weights and the potential negative effect on credit availability, the final rules do not adopt the proposed risk weights, but retain the current risk weights for mortgage exposures under the general risk-based capital rules.

        Consistent with the Dodd-Frank Act, the new rules replace the ratings-based approach to securitization exposures, which is based on external credit ratings, with the simplified supervisory formula approach in order to determine the appropriate risk weights for these exposures. Alternatively, banking organizations may use the existing gross-up approach to assign securitization exposures to a risk weight category or choose to assign such exposures a 1,250 percent risk weight.

        Under the new rules, mortgage servicing assets and certain deferred tax assets are subject to stricter limitations than those applicable under the current general risk-based capital rule. The new rules also increase the risk weights for past due loans, certain commercial real estate loans, and some equity exposures, and makes selected other changes in risk weights and credit conversion factors.

        The Corporation has assessed the impact of these changes to the regulatory capital ratios of the Corporation and ACNB Bank on the capital, operations, liquidity and earnings of the Corporation and ACNB Bank, and concluded that the new rules will not have a material negative effect.

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Table 11—Risk-Based Capital

        The banking subsidiary's capital ratios are as follows:

        For further information on the actual and required capital amounts and ratios, please refer to Note N—"Regulatory Matters" in the Notes to Consolidated Financial Statements.

Liquidity

        Effective liquidity management ensures the cash flow requirements of depositors and borrowers, as well as the operating cash needs of ACNB, are met.

        ACNB's funds are available from a variety of sources, including assets that are readily convertible such as interest bearing deposits with banks, maturities and repayments from the securities portfolio, scheduled repayments of loans receivable, the core deposit base, and the ability to borrow from the FHLB. At December 31, 2017, ACNB could borrow approximately $674,680,200 from the FHLB of which $567,440,200 was available. Because of various restrictions and requirements on utilizing the available balance, ACNB considers $389,000,000 to be the practicable additional borrowing capacity, which is considered to be sufficient for operational needs. The FHLB system is self-capitalizing, member-owned, and its member banks' stock is not publicly traded. ACNB creates its borrowing capacity with the FHLB by granting a security interest in certain loan assets with requisite credit quality. ACNB has reviewed information on the FHLB system and the FHLB of Pittsburgh, and has concluded that they have the capacity and intent to continue to provide both operational and contingency liquidity. The FHLB of Pittsburgh instituted a requirement that a member's investment securities must be moved into a safekeeping account under FHLB control to be considered in the calculation of maximum borrowing capacity. The Corporation currently has securities in safekeeping at the FHLB of Pittsburgh; however, the safekeeping account is under the Corporation's control. As better contingent liquidity is maintained by keeping the securities under the Corporation's control, the Corporation has not moved the securities which, in effect, lowered the Corporation's maximum borrowing capacity. However, there is no practical reduction in borrowing capacity as the securities can be moved into the FHLB-controlled account promptly if they are needed for borrowing purposes.

        Another source of liquidity is securities sold under repurchase agreements to customers of ACNB's banking subsidiary totaling $36,908,000 and $34,590,000 at December 31, 2017 and 2016, respectively. These agreements vary in balance according to the cash flow needs of customers and competing accounts at other financial organizations.

        The liquidity of the parent company also represents an important aspect of liquidity management. The parent company's cash outflows consist principally of dividends to stockholders and corporate expenses. The main source of funding for the parent company is the dividends it receives from its subsidiaries. Federal and state banking regulations place certain legal restrictions and other practicable safety and soundness restrictions on dividends paid to the parent company from the subsidiary bank. For a discussion of ACNB's dividend restrictions, please refer to Item 1—"Business" and Note J—"Regulatory Restrictions on Dividends" in the Notes to Consolidated Financial Statements.

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        ACNB manages liquidity by monitoring projected cash inflows and outflows on a daily basis, and believes it has sufficient funding sources to maintain sufficient liquidity under varying degrees of business conditions.

Aggregate Contractual Obligations

        The following table represents the Corporation's on- and off-balance sheet aggregate contractual obligations to make future payments as of December 31, 2017:

        In addition, the Corporation, in the conduct of business operations, routinely enters into contracts for services and equipment. These contracts may require payment to be provided in the future, and may also contain penalty clauses for early termination of the contracts. Major expenditures are controlled by various approval authorities. Management is not aware of any other commitments or contingent liabilities which may have a material adverse impact on the liquidity or capital resources of the Corporation.

Off-Balance Sheet Arrangements

        The Corporation is party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit and, to a lesser extent, standby letters of credit. At December 31, 2017, the Corporation had unfunded outstanding commitments to extend credit of $264,368,000 and outstanding standby letters of credit of $6,362,000. Because these commitments generally have fixed expiration dates and many will expire without being drawn upon, the total commitment level does not necessarily represent future cash requirements. Please refer to Note O—"Financial Instruments with Off-balance Sheet Risk" in the Notes to Consolidated Financial Statements for a discussion of the nature, business purpose, and importance of the Corporation's off-balance sheet arrangements.

New Accounting Pronouncements

        See Note A—"Summary of Significant Accounting Policies" in the Notes to Consolidated Financial Statements for a summary of these new accounting pronouncements not yet adopted.

ITEM 7A—QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

        Financial institutions can be exposed to several market risks that may impact the value or future earnings capacity of the organization. These risks involve interest rate risk, foreign currency exchange risk, commodity price risk, and equity market price risk. ACNB's primary market risk is interest rate risk. Interest rate risk is inherent because, as a financial institution, ACNB derives a significant amount of its operating revenue from "purchasing" funds (customer deposits and wholesale borrowings) at

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various terms and rates. These funds are then invested into earning assets (primarily loans and investments) at various terms and rates. This risk is further discussed below.

        ACNB does not have any exposure to foreign currency exchange risk, commodity price risk, or equity market risk.

Interest Rate Risk

        Interest rate risk is the exposure to fluctuations in the Corporation's future earnings (earnings at risk) and value (value at risk) resulting from changes in interest rates. This exposure results from differences between the amounts of interest earning assets and interest bearing liabilities that reprice within a specified time period as a result of scheduled maturities and repayment and contractual interest rate changes.

        The primary objective of the Corporation's asset/liability management process is to maximize current and future net interest income within acceptable levels of interest rate risk while satisfying liquidity and capital requirements. Management recognizes that a certain amount of interest rate risk is inherent, appropriate and necessary to ensure the Corporation's profitability. Thus, the goal of interest rate risk management is to maintain a balance between risk and reward such that net interest income is maximized while risk is maintained at a tolerable level.

        Management endeavors to control the exposure to changes in interest rates by understanding, reviewing and making decisions based on its risk position. The banking subsidiary's asset/liability committee is responsible for these decisions. The Corporation primarily uses the securities portfolio and FHLB advances to manage its interest rate risk position. Additionally, pricing, promotion and product development activities are directed in an effort to emphasize the loan and deposit term or repricing characteristics that best meet current interest rate risk objectives. At present, there is no use of hedging instruments.

        The asset/liability committee operates under management policies defining guidelines and limits on the level of risk. These policies are approved by the Board of Directors.

        The Corporation uses simulation analysis to assess earnings at risk and net present value analysis to assess value at risk. These methods allow management to regularly monitor both the direction and magnitude of the Corporation's interest rate risk exposure. These modeling techniques involve assumptions and estimates that inherently cannot be measured with complete precision. Key assumptions in the analyses include maturity and repricing characteristics of both assets and liabilities, prepayments on amortizing assets, non-maturity deposit sensitivity, and loan and deposit pricing. These assumptions are inherently uncertain due to the timing, magnitude and frequency of rate changes and changes in market conditions and management strategies, among other factors. However, the analyses are useful in quantifying risk and provide a relative gauge of the Corporation's interest rate risk position over time.

Earnings at Risk

        Simulation analysis evaluates the effect of upward and downward changes in market interest rates on future net interest income. The analysis involves changing the interest rates used in determining net interest income over the next twelve months. The resulting percentage change in net interest income in various rate scenarios is an indication of the Corporation's short-term interest rate risk. The analysis utilizes a "static" balance sheet approach. The measurement date balance sheet composition (or mix) is maintained over the simulation time period, with maturing and repayment dollars being rolled back into like instruments for new terms at current market rates. Additional assumptions are applied to modify volumes and pricing under the various rate scenarios. These include prepayment assumptions on mortgage assets, sensitivity of non-maturity deposit rates, and other factors deemed significant.

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        The simulation analysis results are presented in Table 13a. These results, as of December 31, 2017, indicate that the Corporation would expect net interest income to increase over the next twelve months by 3.38% assuming an upward ramp in market interest rates of 3.00%, and to decrease by 7.19% if rates ramped downward 3.00%. This profile reflects an acceptable short-term interest rate risk position. However, a decrease of 3.00% would create an environment in which deposit rates could not practically decline further, thus decreasing net interest income.

        Earnings at risk simulations for December 31, 2016, exhibited similar sensitivity in a declining rate environment.

Value at Risk

        The net present value analysis provides information on the risk inherent in the balance sheet that might not be taken into account in the simulation analysis due to the shorter time horizon used in that analysis. The net present value of the balance sheet is defined as the discounted present value of expected asset cash flows minus the discounted present value of the expected liability cash flows. The analysis involves changing the interest rates used in determining the expected cash flows and in discounting the cash flows. The resulting percentage change in net present value in various rate scenarios is an indication of the longer term repricing risk and options embedded in the balance sheet.

        The net present value analysis results are presented in Table 13b. These results, as of December 31, 2017, indicate that the net present value would increase 0.08% assuming an upward shift in market interest rates of 3.00% and increase 1.27% if rates shifted 1.00% in the same manner.

 

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ITEM 8—FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

(a)

The following audited consolidated financial statements and related documents are set forth in this Annual Report on Form 10-K on the following pages:

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Stockholders and Board of Directors
ACNB Corporation
Gettysburg, Pennsylvania

Opinion on the Consolidated Financial Statements

        We have audited the accompanying consolidated statements of condition of ACNB Corporation (the Corporation) as of December 31, 2017 and 2016, the related consolidated statements of income, comprehensive income, changes in stockholders' equity, and cash flows for each of the three years in the period ended December 31, 2017, and the related notes (collectively referred to as the consolidated financial statements). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Corporation at December 31, 2017 and 2016, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2017, in conformity with accounting principles generally accepted in the United States of America.

        We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Corporation's internal control over financial reporting as of December 31, 2017, based on criteria established in the Internal Control—Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO), and our report dated March 9, 2018, expressed an unqualified opinion thereon.

Basis for Opinion

        These consolidated financial statements are the responsibility of the Corporation's management. Our responsibility is to express an opinion on the Corporation's consolidated financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Corporation in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

        We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud.

        Our audits included performing procedures to assess the risk of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

/s/ BDO USA, LLP

We have served as the Corporation's auditor since 2013.

Harrisburg, Pennsylvania
March 9, 2018

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ACNB CORPORATION

CONSOLIDATED STATEMENTS OF CONDITION

   

The accompanying notes are an integral part of the consolidated financial statements.

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ACNB CORPORATION

CONSOLIDATED STATEMENTS OF INCOME

   

The accompanying notes are an integral part of the consolidated financial statements.

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ACNB CORPORATION

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

   

The accompanying notes are an integral part of the consolidated financial statements.

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ACNB CORPORATION

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY

Years Ended December 31, 2017, 2016 and 2015

   

The accompanying notes are an integral part of the consolidated financial statements.

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ACNB CORPORATION

CONSOLIDATED STATEMENTS OF CASH FLOWS

   

The accompanying notes are an integral part of the consolidated financial statements.

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ACNB CORPORATION

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Nature of Operations

        ACNB Corporation (the Corporation or ACNB), headquartered in Gettysburg, Pennsylvania, provides banking, insurance, and financial services to businesses and consumers through its wholly-owned subsidiaries, ACNB Bank (Bank) and Russell Insurance Group, Inc. (RIG). The Bank engages in full-service commercial and consumer banking and wealth management services, including trust and retail brokerage, through its twenty-two community banking locations in Adams, Cumberland, Franklin, and York Counties, Pennsylvania. There is also a loan production office situated in York County, Pennsylvania.

        On July 1, 2017, ACNB completed its acquisition of New Windsor Bancorp, Inc. (New Windsor) of Taneytown, Maryland. At the effective time of the acquisition, New Windsor merged with and into a wholly-owned subsidiary of ACNB, immediately followed by the merger of New Windsor State Bank (NWSB) with and into ACNB Bank. ACNB Bank now operates in the Maryland market as "NWSB Bank, A Division of ACNB Bank" and serves its marketplace with banking and wealth management services via a network of seven community banking offices located in Carroll County, Maryland.

        RIG is a full-service insurance agency based in Westminster, Maryland with a second location in Germantown, Maryland. The agency offers a broad range of property and casualty, life, and health insurance to both commercial and individual clients.

        The Corporation's primary source of revenue is interest income on loans and investment securities and fee income on its products and services. Expenses consist of interest expense on deposits and borrowed funds, provisions for loan losses, and other operating expenses.

Basis of Financial Statements

        The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) and include the accounts of the Corporation and its wholly-owned subsidiaries. All significant intercompany transactions have been eliminated.

        Assets held by the Corporation's Wealth management Department, including trust and retail brokerage, in an agency, fiduciary or retail brokerage capacity for its customers are excluded from the consolidated financial statements since they do not constitute assets of the Corporation. Assets held by the Wealth Management Department amounted to $327,000,000 and $195,000,000 at December 31, 2017 and 2016, respectively. Income from fiduciary, investment management and brokerage activities are included in other income.

        The Corporation has evaluated events and transactions occurring subsequent to the balance sheet date of December 31, 2017, for items that should potentially be recognized or disclosed in the consolidated financial statements. The evaluation was conducted through the date these consolidated financial statements were issued.

Use of Estimates

        Financial statements prepared in accordance with GAAP require management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingencies at the date of the consolidated financial statements, and revenues and expenses during

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ACNB CORPORATION

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

the reporting period. Actual results could differ from these estimates. Material estimates that are particularly susceptible to significant change in the near term relate to the determination of the allowance for loan losses, the determination of other than temporary impairment on securities, and the potential impairment of goodwill.

Significant Group Concentrations of Credit Risk

        Most of the Corporation's activities are with customers located within southcentral Pennsylvania and northern Maryland. Note C discusses the types of securities in which the Corporation invests. Note D discusses the types of lending in which the Corporation engages. Included in commercial real estate loans are loans made to lessors of non-residential dwellings that total $269,080,000, or 21.6%, of total loans at December 31, 2017. These borrowers are geographically disbursed throughout ACNB's marketplace and are leasing commercial properties to a varied group of tenants including medical offices, retail space and recreational facilities. Because of the varied nature of the tenants in aggregate, management believes that these loans do not present any greater risk than commercial loans in general.

Cash and Cash Equivalents

        For purposes of the consolidated statements of cash flows, cash and cash equivalents include cash on hand, balances due from banks, and federal funds sold, all of which mature within 90 days.

Securities

        Debt securities that management has the positive intent and ability to hold to maturity are classified as "held to maturity" and recorded at amortized cost. Securities not classified as held to maturity or trading, including equity securities with readily determinable fair values, are classified as "available for sale" and recorded at fair value, with unrealized gains and losses excluded from earnings and reported, net of tax, in other comprehensive income (loss).

        Purchase premiums and discounts are recognized in interest income using the interest method over the terms of the securities. Declines in the fair value of held to maturity and available for sale securities below their cost that are deemed to be other than temporary are reflected in earnings as realized losses. In estimating other-than-temporary impairment losses on debt securities, management considers (1) whether management intends to sell the security, or (2) if it is more likely than not that management will be required to sell the security before recovery, or (3) if management does not expect to recover the entire amortized cost basis. In assessing potential other-than-temporary impairment for equity securities, consideration is given to management's intention and ability to hold the securities until recovery of unrealized losses. Gains and losses on the sale of securities are recorded on the trade date and are determined using the specific identification method.

Loans Held for Sale

        Loans originated and intended for sale in the secondary market are carried at the lower of aggregate cost or fair value, as determined by aggregate outstanding commitments from investors or current investor yield requirements. Net unrealized losses are recognized through a valuation allowance by charges to income.

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ACNB CORPORATION

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

        Mortgage loans held for sale are sold with the mortgage servicing rights released to another financial institution through a correspondent relationship. The correspondent financial institution absorbs all of the risk related to rate lock commitments. Gains or losses on sales of mortgage loans are recognized based on the difference between the selling price and the carrying value of the related mortgage loans sold.

Loans

        The Corporation grants commercial, residential, and consumer loans to customers. A substantial portion of the loan portfolio is represented by mortgage loans throughout southcentral Pennsylvania and northern Maryland. The ability of the Corporation's debtors to honor their contracts is dependent upon the real estate values and general economic conditions in this area.

        Loans that management has the intent and ability to hold for the foreseeable future or until maturity or pay-off generally are reported at their outstanding unpaid principal balances adjusted for charge-offs, the allowance for loan losses, and any deferred fees or costs on originated loans. Interest income is accrued on the unpaid principal balance. Loan origination fees, net of certain direct origination costs, are deferred and recognized as an adjustment of the related loan yield using the interest method.

        The loans receivable portfolio is segmented into commercial, residential mortgage, home equity lines of credit, and consumer loans. Commercial loans consist of the following classes: commercial and industrial, commercial real estate, and commercial real estate construction.

        The accrual of interest on residential mortgage and commercial loans is discontinued at the time the loan is 90 days past due unless the credit is well-secured and in process of collection. Consumer loans (consisting of home equity lines of credit and consumer loan classes) are typically charged off no later than 120 days past due. Past due status is based on the contractual terms of the loan. In all cases, loans are placed on nonaccrual or charged off at an earlier date if collection of principal or interest is considered doubtful.

        All interest accrued, but not collected, for loans that are placed on nonaccrual or charged off is reversed against interest income. The interest on these loans is accounted for on the cash-basis or cost-recovery method, until qualifying for return to accrual status. Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured.

Allowance for Credit Losses

        The allowance for credit losses consists of the allowance for loan losses and the reserve for unfunded lending commitments. The allowance for loan losses (the "allowance") is established as losses are estimated to occur through a provision for loan losses charged to earnings. Loan losses are charged against the allowance when management believes the uncollectibility of a loan balance is confirmed. Subsequent recoveries, if any, are credited to the allowance. The reserve for unfunded lending commitments represents management's estimate of losses inherent in its unfunded loan commitments and is recorded in other liabilities on the consolidated statement of condition. The amount of the reserve for unfunded lending commitments is not material to the consolidated financial statements.

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ACNB CORPORATION

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

        The allowance for loan losses is evaluated on a regular basis by management and is based upon management's periodic review of the collectibility of the loans in light of historical experience, the nature and volume of the loan portfolio, adverse situations that may affect the borrower's ability to repay, estimated value of any underlying collateral, and prevailing economic conditions. This evaluation is inherently subjective as it requires estimates that are susceptible to significant revision as more information becomes available.

        The allowance consists of specific, general and unallocated components. The specific component relates to loans that are classified as either doubtful, substandard, or special mention. For such loans that are also classified as impaired, an allowance is established when the discounted cash flows (or collateral value or observable market price) of the impaired loan is lower than the carrying value of that loan. The general component covers pools of loans by loan class including commercial loans not considered impaired, as well as smaller balance homogeneous loans, such as residential real estate, home equity, and other consumer loans. These pools of loans are evaluated for loss exposure based upon historical loss rates for each of these categories of loans, adjusted for qualitative factors. These qualitative risk factors include:

•

lending policies and procedures, including underwriting standards and collection, charge-off and recovery practices;



•

national, regional and local economic and business conditions, as well as the condition of various market segments, including the impact on the value of underlying collateral for collateral dependent loans;



•

the nature and volume of the portfolio and terms of loans;



•

the experience, ability and depth of lending management and staff;



•

the volume and severity of past due, classified and nonaccrual loans, as well as other loan modifications; and,



•

the existence and effect of any concentrations of credit and changes in the level of such concentrations.

        Each factor is assigned a value to reflect improving, stable or declining conditions based on management's best judgment using relevant information available at the time of the evaluation. Adjustments to the factors are supported through documentation of changes in conditions in a narrative accompanying the allowance for loan loss calculation.

        The unallocated component of the allowance is maintained to cover uncertainties that could affect management's estimate of probable losses. The unallocated component of the allowance reflects the margin of imprecision inherent in the underlying assumptions used in the methodologies for estimating specific and general losses in the portfolio. It covers risks that are inherently difficult to quantify including, but not limited to, collateral risk, information risk, and historical charge-off risk.

        A loan is considered impaired when, based on current information and events, it is probable that the Corporation will be unable to collect the scheduled payments of principal and/or interest when due according to the contractual terms of the loan agreement. Factors considered by management in determining impairment include payment status, collateral value, and the probability of collecting scheduled principal and/or interest payments when due. Loans that experience insignificant payment

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ACNB CORPORATION

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

delays and payment shortfalls generally are not classified as impaired. Management determines the significance of payment delays and payment shortfalls on a case-by-case basis, taking into consideration all of the circumstances surrounding the loan and the borrower, including the length of the delay, the reasons for the delay, the borrower's prior payment record, and the amount of the shortfall in relation to the principal and interest owed. Impairment is measured on a loan by loan basis for commercial and commercial construction loans by either the present value of expected future cash flows discounted at the loan's effective interest rate, the loan's obtainable market price, or the fair value of the collateral if the loan is collateral dependent.

        A specific allocation within the allowance for loan losses is established for an impaired loan if its carrying value exceeds its estimated fair value. The estimated fair values of the Corporation's impaired loans are measured based on the estimated fair value of the loan's collateral or the discounted cash flows method.

        It is the policy of the Corporation to order an updated valuation on all real estate secured loans when the loan becomes 90 days past due and there has not been an updated valuation completed within the previous 12 months. In addition, the Corporation orders third-party valuations on all impaired real estate collateralized loans within 30 days of the loan being classified as impaired. Until the valuations are completed, the Corporation utilizes the most recent independent third-party real estate valuation to estimate the need for a specific allocation to be assigned to the loan. These existing valuations are discounted downward to account for such things as the age of the existing collateral valuation, change in the condition of the real estate, change in local market and economic conditions, and other specific factors involving the collateral. Once the updated valuation is completed, the collateral value is updated accordingly.

        For commercial and industrial loans secured by non-real estate collateral, such as accounts receivable, inventory and equipment, estimated fair values are determined based on the borrower's financial statements, inventory reports, accounts receivable aging reports, equipment appraisals, or invoices. Indications of value from these sources are generally discounted based on the age of the financial information or the quality of the assets.

        The Corporation actively monitors the values of collateral as well as the age of the valuation of impaired loans. Management believes that the Corporation's market area is not as volatile as other areas throughout the United States, therefore valuations are ordered at least every 18 months, or more frequently if management believes that there is an indication that the fair value has declined.

        For impaired loans secured by collateral other than real estate, the Corporation considers the net book value of the collateral, as recorded in the most recent financial statements of the borrower, and determines fair value based on estimates made by management.

        Large groups of smaller balance homogeneous loans are collectively evaluated for impairment. Accordingly, the Corporation does not separately identify individual consumer and residential loans for impairment disclosures, unless such loans are the subject of a troubled debt restructure.

        Loans whose terms are modified are classified as troubled debt restructured loans if the Corporation grants such borrowers concessions that it would not otherwise consider and it is deemed that those borrowers are experiencing financial difficulty. Concessions granted under a troubled debt restructuring generally involve a temporary reduction in interest rate, a below market interest rate given the risk associated with the loan, or an extension of a loan's stated maturity date. Nonaccrual

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ACNB CORPORATION

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

troubled debt restructurings may be restored to accrual status if principal and interest payments, under the modified terms, are current for a sustained period of time and, based on a well-documented credit evaluation of the borrower's financial condition, there is reasonable assurance of repayment. Loans classified as troubled debt restructurings are generally designated as impaired.

        The allowance calculation methodology includes further segregation of loan classes into credit quality rating categories. The borrower's overall financial condition, repayment sources, guarantors, and value of collateral, if appropriate, are generally evaluated annually for commercial loans or when credit deficiencies arise, such as delinquent loan payments.

        Credit quality risk ratings include regulatory classifications of special mention, substandard, doubtful and loss. Loans classified special mention have potential weaknesses that deserve management's close attention. If uncorrected, the potential weaknesses may result in deterioration of the repayment prospects. Loans classified substandard have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They include loans that are inadequately protected by the current sound net worth and paying capacity of the obligor or of the collateral pledged, if any. Loans classified doubtful have all the weaknesses inherent in loans classified substandard with the added characteristic that collection or liquidation in full, on the basis of current conditions and facts, is highly improbable. Loans classified as a loss are considered uncollectible and are charged to the allowance for loan losses. Loans not classified are rated pass.

        In addition, federal and state regulatory agencies, as an integral part of their examination process, periodically review the Corporation's allowance for loan losses and may require the Corporation to recognize additions to the allowance based on their judgments about information available to them at the time of their examination, which may not be currently available to management. Based on management's comprehensive analysis of the loan portfolio and economic conditions, management believes the current level of the allowance for loan losses is adequate.

        Commercial and Industrial Lending—The Corporation originates commercial and industrial loans primarily to businesses located in its primary market area and surrounding areas. These loans are used for various business purposes which include short-term loans and lines of credit to finance machinery and equipment purchases, inventory, and accounts receivable. Generally, the maximum term for loans extended on machinery and equipment is based on the projected useful life of such machinery and equipment. Most business lines of credit are written on demand and may be renewed annually.

        Commercial and industrial loans are generally secured with short-term assets; however, in many cases, additional collateral such as real estate is provided as additional security for the loan. Loan-to-value maximum values have been established by the Corporation and are specific to the type of collateral. Collateral values may be determined using invoices, inventory reports, accounts receivable aging reports, collateral appraisals, etc.

        In underwriting commercial and industrial loans, an analysis is performed to evaluate the borrower's character and capacity to repay the loan, the adequacy of the borrower's capital and collateral, as well as the conditions affecting the borrower. Evaluation of the borrower's past, present and future cash flows is also an important aspect of the Corporation's analysis.

        Commercial loans generally present a higher level of risk than other types of loans due primarily to the effect of general economic conditions.

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ACNB CORPORATION

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

        Commercial Real Estate Lending—The Corporation engages in commercial real estate lending in its primary market area and surrounding areas. The Corporation's commercial loan portfolio is secured primarily by commercial retail space, office buildings, and hotels. Generally, commercial real estate loans have terms that do not exceed 20 years, have loan-to-value ratios of up to 80% of the appraised value of the property, and are typically secured by personal guarantees of the borrowers.

        In underwriting these loans, the Corporation performs a thorough analysis of the financial condition of the borrower, the borrower's credit history, and the reliability and predictability of the cash flow generated by the property securing the loan. Appraisals on properties securing commercial real estate loans originated by the Corporation are performed by independent appraisers.

        Commercial real estate loans generally present a higher level of risk than other types of loans due primarily to the effect of general economic conditions and the complexities involved in valuing the underlying collateral.

        Commercial Real Estate Construction Lending—The Corporation engages in commercial real estate construction lending in its primary market area and surrounding areas. The Corporation's commercial real estate construction lending consists of commercial and residential site development loans, as well as commercial building construction and residential housing construction loans.

        The Corporation's commercial real estate construction loans are generally secured with the subject property. Terms of construction loans depend on the specifics of the project, such as estimated absorption rates, estimated time to complete, etc.

        In underwriting commercial real estate construction loans, the Corporation performs a thorough analysis of the financial condition of the borrower, the borrower's credit history, and the reliability and predictability of the cash flow generated by the project using feasibility studies, market data, etc. Appraisals on properties securing commercial real estate construction loans originated by the Corporation are performed by independent appraisers.

        Commercial real estate construction loans generally present a higher level of risk than other types of loans due primarily to the effect of general economic conditions and the uncertainties surrounding total construction costs.

        Residential Mortgage Lending—One-to-four family residential mortgage loan originations, including home equity closed-end loans, are generated by the Corporation's marketing efforts, its present customers, walk-in customers, and referrals. These loans originate primarily within the Corporation's market area or with customers primarily from the market area.

        The Corporation offers fixed-rate and adjustable-rate mortgage loans with terms up to a maximum of 30 years for both permanent structures and those under construction. The Corporation's one-to-four family residential mortgage originations are secured primarily by properties located in its primary market area and surrounding areas. The majority of the Corporation's residential mortgage loans originate with a loan-to-value of 80% or less. Loans in excess of 80% are required to have private mortgage insurance.

        In underwriting one-to-four family residential real estate loans, the Corporation evaluates both the borrower's financial ability to repay the loan as agreed and the value of the property securing the loan. Properties securing real estate loans made by the Corporation are appraised by independent appraisers.

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The Corporation generally requires borrowers to obtain an attorney's title opinion or title insurance, as well as fire and property insurance (including flood insurance, if necessary) in an amount not less than the amount of the loan. The Corporation has not engaged in subprime residential mortgage originations.

        Residential mortgage loans present a moderate level of risk due primarily to general economic conditions, as well as a continued weak housing market.

        Home Equity Lines of Credit Lending—The Corporation originates home equity lines of credit primarily within the Corporation's market area or with customers primarily from the market area. Home equity lines of credit are generated by the Corporation's marketing efforts, its present customers, walk-in customers, and referrals.

        Home equity lines of credit are secured by the borrower's primary residence with a maximum loan-to-value of 90% and a maximum term of 20 years. In underwriting home equity lines of credit, the Corporation evaluates both the value of the property securing the loan and the borrower's financial ability to repay the loan as agreed. The ability to repay is determined by the borrower's employment history, current financial condition, and credit background.

        Home equity lines of credit generally present a moderate level of risk due primarily to general economic conditions, as well as a continued weak housing market.

        Junior liens inherently have more credit risk by virtue of the fact that another financial institution may have a higher security position in the case of foreclosure liquidation of collateral to extinguish the debt. Generally, foreclosure actions could become more prevalent if the real estate market continues to be weak and property values deteriorate.

        Consumer Lending—The Corporation offers a variety of secured and unsecured consumer loans, including those for vehicles and mobile homes and loans secured by savings deposits. These loans originate primarily within the Corporation's market area or with customers primarily from the market area.

        Consumer loan terms vary according to the type and value of collateral and the creditworthiness of the borrower. In underwriting consumer loans, a thorough analysis of the borrower's financial ability to repay the loan as agreed is performed. The ability to repay is determined by the borrower's employment history, current financial condition, and credit background.

        Consumer loans may entail greater credit risk than residential mortgage loans or home equity lines of credit, particularly in the case of consumer loans which are unsecured or are secured by rapidly depreciable assets such as automobiles or recreational equipment. In such cases, any repossessed collateral for a defaulted consumer loan may not provide an adequate source of repayment of the outstanding loan balance as a result of the greater likelihood of damage, loss or depreciation. In addition, consumer loan collections are dependent on the borrower's continuing financial stability, and thus are more likely to be affected by adverse personal circumstances. Furthermore, the application of various federal and state laws, including bankruptcy and insolvency laws, may limit the amount which can be recovered on such loans.

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Acquired Loans

        Acquired Loans (impaired and non-impaired) are initially recorded at their acquisition-date fair values using Level 3 inputs. Fair values are based on a discounted cash flow methodology that involves assumptions and judgments as to credit risk, expected lifetime losses, environmental factors, collateral values, discount rates, expected payments and expected prepayments. Specifically, the Corporation has prepared three separate loan fair value adjustments that it believed a market participant might employ in estimating the entire fair value adjustment necessary under ASC 820-10 for the acquired loan portfolio. The three-separate fair valuation methodology employed are: 1) an interest rate loan fair value adjustment (analysis available at request of the Corporation), 2) a general credit fair value adjustment (analysis available at request of the Corporation) and 3) a specific credit fair value adjustment for purchased credit impaired loans subject to ASC 310-30 procedures.

        The carryover of allowance for loan losses related to acquired loans is prohibited as any credit losses in the loans are included in the determination of the fair value of the loans at the acquisition date. The allowance for loan losses on acquired loans reflects only those losses incurred after acquisition and represents the present value of cash flows expected at acquisition that is no longer expected to be collected. Acquired loans are marked to fair value on the date of acquisition. In conjunction with the quarterly evaluation of the adequacy of the allowance for loan losses, the Corporation performs an analysis on acquired loans to determine whether or not there has been subsequent deterioration in relation to those loans. If deterioration has occurred, the Corporation will includes these loans in the calculation of the allowance for loan losses after the initial valuation, and provide accordingly.

        Upon acquisition, in accordance with Generally Accepted Accounting Principles, the Corporation has individually determined whether each acquired loan is within the scope of ASC 310-30. The Corporation's senior lending management reviewed the accounting seller's loan portfolio on a loan by loan basis to determine if any loans met the two-part definition of an impaired loan as defined by ASC 310-30: 1) Credit deterioration on the loan from its inception until the acquisition date, and 2) It is probable that not all of the contractual cash flows will be collected on the loan.

        Any acquired loans that were not individually in the scope of ASC 310-30 because they did not meet the criteria above were pooled into groups of similar loans based on various factors including borrower type, loan purpose, and collateral type. For these pools, we used certain loan information, including outstanding principal balance, estimated expected losses, weighted average maturity, weighted average margin, and weighted average interest rate along with estimated prepayment rates, expected lifetime losses, environment factors to estimate the expected cash flow for each loan pool. With regards to ASC 310-30 loans, for external disclosure purposes, the aggregate contractual cash flows less the aggregate expected cash flows will result in a credit related non-accretable yield amount. The aggregate expected cash flows less the acquisition date fair value will result in an accretable yield amount. The accretable yield reflects the contractual cash flows management expects to collect about the loan's acquisition date fair value and will be recognized over the life of the loan on a level-yield basis as a component of interest income.

        Over the life of the acquired ASC 310-30 loan, we continue to estimate cash flows expected to be collected. Decreases in expected cash flows, other than from prepayments or rate adjustments, are recognized as impairments through a charge to the provision for credit losses resulting in an increase in the allowance for credit losses. Subsequent improvements in cash flows result in first, reversal of

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existing valuation allowances recognized subsequent to acquisition, if any, and next, an increase in the amount of accretable yield to be subsequently recognized on a prospective basis over the loan's remaining life.

        Acquired ASC 310-30 loans that met the criteria for non-accrual of interest prior to acquisition are considered performing upon acquisition, regardless of whether the customer is contractually delinquent, if we can reasonably estimate the timing and amount of expected cash flows on such loans. Accordingly, we do not consider acquired contractually delinquent loans to be non-accruing and continue to recognize interest income on these loans using the accretion model.

        For loans acquired without evidence of credit quality deterioration, ACNB prepared the interest rate loan fair value and credit fair value adjustments. Loans were grouped into homogeneous pools by characteristics such as loan type, term, collateral, and rate. Market rates for similar loans were obtained from various internal and external data sources and reviewed by management for reasonableness. The average of these rates was used as the fair value interest rate a market participant would utilize. A present value approach was utilized to calculate the interest rate fair value discount of $731,000.

        Additionally, for loans acquired without credit quality deterioration, a credit fair value adjustment was calculated using a two-part credit fair value analysis: 1) expected lifetime credit migration losses; and 2) estimated fair value adjustment for certain qualitative factors. The expected lifetime losses were calculated using historical losses observed at the Bank, NWSB and peer banks. ACNB also estimated an environmental factor to apply to each loan type. The environmental factor represents potential discount which may arise due to general credit and economic factors. A credit fair value discount of $4.5 million was determined. Both the interest rate and credit fair value adjustments relate to loans acquired with evidence of credit quality deterioration will be substantially recognized as interest income on a level yield amortization method over the expected life of the loans.

Premises and Equipment

        Land is carried at cost. Buildings, furniture, fixtures, equipment and leasehold improvements are carried at cost, less accumulated depreciation. Depreciation is computed principally by the straight-line method over the assets' estimated useful lives. Normally, a buildings useful life is 40 years, except for building remodels and additions, which are depreciated over fifteen years. Bank equipment, including furniture and fixtures, is normally depreciated over five - fifteen years depending upon the nature of the purchase. Maintenance and normal repairs are charged to expense when incurred while major additions and improvements are capitalized. Gains and losses on disposals are reflected in current operations. Amortization of leasehold improvements is computed by straight line over the shorter of the assets' useful life or the related lease term.

Restricted Investment in Bank Stocks

        Restricted investment in bank stocks, which represents required investments in the common stock of correspondent banks, is carried at cost as of December 31, 2017 and 2016, and consists of common stock in the Atlantic Central Bankers Bank, Maryland Financial Bank, Community Bankers Bank and Federal Home Loan Bank (FHLB).

        Management evaluates the restricted investment in bank stocks for impairment in accordance with Accounting Standard Codification (ASC) Topic 942, Financial Services—Depository and Lending.

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Management's determination of whether these investments are impaired is based on their assessment of the ultimate recoverability of their cost rather than by recognizing temporary declines in value. The determination of whether a decline affects the ultimate recoverability of their cost is influenced by criteria such as (1) the significance of the decline in net assets of the correspondent bank as compared to the capital stock amount for the correspondent bank and the length of time this situation has persisted, (2) commitments by the correspondent bank to make payments required by law or regulation and the level of such payments in relation to the operating performance of the correspondent bank, (3) the impact of legislative and regulatory changes on institutions and, accordingly, on the customer base of the correspondent bank, and (4) the liquidity position of the correspondent bank.

        Management believes no impairment charge was necessary related to the restricted investment in bank stocks during 2017, 2016 or 2015. However, security impairment analysis is completed quarterly, and the determination that no impairment has occurred during those years is no assurance that impairment may not occur in future periods.

Bank-Owned Life Insurance

        The Corporation's banking subsidiary maintains nonqualified compensation plans for selected senior officers. To fund the benefits under these plans, the Bank is the owner of single premium life insurance policies on participants in the nonqualified retirement plans. Investment in bank-owned life insurance policies was used to finance the nonqualified compensation plans and provide tax-exempt income to the Corporation.

        ASC Topic 715, Compensation—Retirement Benefits, requires a liability to be recorded during the service period when a split-dollar life insurance agreement continues after participants' employment or retirement. The required accrued liability is based on either the post-employment benefit cost for continuing life insurance or based on the future death benefit depending on the contractual terms of the underlying agreement. The Corporation's liability is based on the post-employment benefit cost for continuing life insurance. The Corporation incurred approximately $96,000, $96,000, and $46,000 of expense in 2017, 2016, and 2015, respectively, related to these benefits.

Investments in Low-Income Housing Partnerships

        The Corporation's investments in low-income housing partnerships are accounted for using the "equity method" prescribed by ASC Topic 323, Investments—Equity Method. In accordance with ASC Topic 740, Income Taxes, tax credits are recognized as they become available. Any residual loss is amortized as the tax credits are received.

Goodwill and Intangible Assets

        The Corporation accounts for its acquisitions using the acquisition accounting method required by ASC Topic 805, Business Combinations. Acquisition accounting requires the total purchase price to be allocated to the estimated fair values of assets and liabilities acquired, including certain intangible assets that must be recognized. Generally, this results in a residual amount in excess of the net fair values, which is recorded as goodwill.

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        ASC Topic 350, Intangibles—Goodwill and Other, requires that goodwill is not amortized to expense, but rather that it be assessed for impairment at least annually. If certain events occur which might indicate goodwill has been impaired, the goodwill is tested for impairment when such events occur. Impairment write-downs are charged to results of operations in the period in which the impairment is determined. The Corporation did not identify any impairment on RIG's outstanding goodwill from its most recent testing, which was performed as of October 1, 2017. The Corporation has not identified any such events, and, accordingly, has not tested goodwill resulting from the acquisition of New Windsor for impairment during the year ended December 31, 2017. ACNB plans on testing New Windsor goodwill during 2018. Other acquired intangible assets with finite lives, such as customer lists, are required to be amortized over the estimated lives. These intangibles are generally amortized using the straight line method over estimated useful lives of five to fifteen years.

Foreclosed Assets

        Assets acquired through, or in lieu of, loan foreclosure are held for sale and are initially recorded at fair value, less costs to sell at the date of foreclosure, establishing a new cost basis. Subsequent to foreclosure, valuations are periodically performed by management and the assets are adjusted to the fair value, less costs to sell as necessary. Revenue and expenses from operations and changes in the valuation allowance are included in net expenses from foreclosed assets. $264,000 of the $436,000 outstanding foreclosed asset balance held at December 31, 2017 represent residential real estate properties.

Income Taxes

        The Corporation accounts for income taxes in accordance with income tax accounting guidance ASC Topic 740, Income Taxes.

        Current income tax accounting guidance results in two components of income tax expense: current and deferred. Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of the enacted tax law to the taxable income or excess of deductions over revenues. The Corporation determines deferred income taxes using the liability (or balance sheet) method. Under this method, the net deferred tax asset or liability is based on the tax effects of the differences between the book and tax bases of assets and liabilities, and enacted changes in tax rates and laws are recognized in the period in which they occur.

        Deferred income tax expense results from changes in deferred tax assets and liabilities between periods. Deferred tax assets are reduced by a valuation allowance if, based on the weight of the evidence available, it is more likely than not that some portion or all of a deferred tax asset will not be realized.

        The Corporation accounts for uncertain tax positions if it is more likely than not, based on the technical merits, that the tax position will be realized or sustained upon examination. The term more-likely-than-not means a likelihood of more than 50%; the terms examined and upon examination also include resolution of the related appeals or litigation processes, if any. A tax position that meets the more-likely-than-not recognition threshold is initially and subsequently measured as the largest amount of tax benefit that has a greater than 50% likelihood of being realized upon settlement with a taxing authority that has full knowledge of all relevant information. The determination of whether or not a tax position has met the more-likely-than-not recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to management's judgment.

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        The Corporation recognizes interest and penalties on income taxes, if any, as a component of income tax expense.

Retirement Plan

        The compensation cost of an employee's pension benefit is recognized on the projected unit credit method over the employee's approximate service period. The aggregate cost method is utilized for funding purposes.

Stock-based Compensation

        ACNB Corporation has a Restricted Stock plan available to selected officers and employees of the Bank, to advance the best interest of ACNB Corporation and its shareholders. The plan provides those persons who have responsibility for its growth with additional incentive by allowing them to acquire an ownership in ACNB Corporation and thereby encouraging them to contribute to the success of the Corporation. Plan expense is recognized over the vesting period of the stock issued under the plan. To date, 19,301 shares were issued under this plan, which resulted in $133,000 and $59,000 of compensation expense for the year ended December 31, 2017 and 2016, respectively. Of the 19,301 shares issued under the plan, 13,235 shares are fully vested and 6,066 will vest over the next two years.

Net Income per Share

        The Corporation has a simple capital structure. Basic earnings per share of common stock is computed based on 6,543,756, 6,051,579 and 6,026,224 weighted average shares of common stock outstanding for 2017, 2016 and 2015, respectively. All outstanding unvested restricted stock awards that contain rights to nonforfeitable dividends are considered participating for this calculation.

Advertising Costs

        Costs of advertising, which are included in marketing expenses, are expensed when incurred.

Off-Balance Sheet Credit-Related Financial Instruments

        In the ordinary course of business, the Corporation has entered into commitments to extend credit, including commitments under commercial lines of credit, and standby letters of credit. Such financial instruments are recorded when they are funded.

Transfers of Financial Assets

        Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when (1) the assets have been isolated from the Corporation, (2) the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and (3) the Corporation does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity or the ability to unilaterally cause the holder to return specific assets.

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Accumulated Other Comprehensive Loss

        The components of the accumulated other comprehensive loss, net of taxes, are as follows:

Segment Reporting

        The Bank acts as an independent community financial services provider, which offers traditional banking and related financial services to individual, business, and government customers. Through its branch and automated teller machine networks, the Bank offers a full array of commercial and community financial services, including the taking of time, savings, and demand deposits; the making of commercial, consumer, and mortgage loans; and the providing of other financial services. Management does not separately allocate expenses, including the cost of funding loan demand, between the commercial, community and mortgage banking operations of the Bank. As such, discrete financial information for commercial, community and mortgage banking operations is not available and segment reporting would not be meaningful. Please refer to Note S—"Segment and Related Information" for a discussion of insurance operations.

New Accounting Pronouncements

ASU 2014-09, 2015-14, 2016-08, 2016-12, 2016-20, and 2017-10

        In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606), superseding the revenue recognition requirements in ASC 605. This ASU requires an entity to recognize revenue for the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The amendment includes a five-step process to assist an entity in achieving the main principle(s) of revenue recognition under ASC 605. In March 2016, the FASB also issued ASU 2016-08, an amendment to the guidance in ASU 2014-09, which reframed the structure of the indicators of when an entity is acting as an agent and focused on evidence that an entity is acting as the principal or agent in a revenue transaction. ASU 2016-08 also eliminated two of the indicators (the entity's consideration is in the form of a commission, and the entity is not exposed to credit risk) in making that determination. This amendment also clarifies that each indicator may be more or less relevant to the assessment depending on the terms and conditions of the contract. In May 2016, the FASB issued ASU 2016-12, and amendment to ASU 2014-09, which provided practical expedients related to disclosures of remaining performance obligations, as well as other amendments to guidance on transition, collectability, non-cash consideration and presentation of sales and other similar taxes. The amendments, collectively, should be applied retrospectively to each prior reporting period presented or as a cumulative effect adjustment as of the date of adoption (modified retrospective approach).

        The Corporation's revenue is comprised of net interest income on financial assets and financial liabilities, which is explicitly excluded from the scope of ASU 2014-09, and non-interest income. With respect to non-interest income, the Corporation has identified revenue streams within the scope of the guidance, and has performed an evaluation of the underlying revenue contracts. The Corporation's overall assessment indicates that adoption of this ASU will not materially change its current method

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and timing of recognizing revenue for the identified revenue streams. The Corporation, however, is still in process of developing additional quantitative and qualitative disclosures that are required upon the adoption of the new revenue recognition standard as well as evaluating certain revenue streams for principal verus agent treatment of the related revenue (i.e., reporting revenues on a gross basis or net of related expenses). The Corporation adopted this ASU on January 1, 2018, on a cumulative effect approach. The adoption of this ASU, as discussed above, did not have a significant impact on the Corporation's financial condition, results of operations and consolidated financial statements.

ASU 2016-01

        In January 2016, the FASB issued ASU 2016-01, Financial Instruments—Overall (Topic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities.

        ASU 2016-01 amends the guidance on the classification and measurement of financial instruments. Some of the amendments in ASU 2016-01 include the following among others: (i) requires equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income; (ii) simplifies the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment; (iii) requires public business entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes; and, (iv) requires an entity to present separately in other comprehensive income the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value.

        For public business entities, the amendments of ASU 2016-01 are effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years.

        The Corporation had determined this ASU will not have a material effect on its consolidated financial condition or results of operations when adopted on January 1, 2018.

ASU 2016-02

        In February 2016, the FASB issued ASU 2016-02, Leases.

        From the lessee's perspective, the new standard establishes a right-of-use (ROU) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement for a lessee. From the lessor's perspective, the new standard requires a lessor to classify leases as either sales-type, finance or operating. A lease will be treated as a sale if it transfers all of the risks and rewards, as well as control of the underlying asset, to the lessee. If risks and rewards are conveyed without the transfer of control, the lease is treated as a financing lease. If the lessor doesn't convey risks and rewards or control, an operating lease results.

        The new standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. A modified retrospective transition approach is required for lessors for sales-type, direct financing, and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available.

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        While the Corporation is currently evaluating the timing and impact of adopting ASU 2016-02, the ultimate impact of adopting ASU 2016-02 will depend on the Corporation's lease portfolio as of the adoption date and interest rates at that time. The Corporation expects to recognize right-of-use assets and lease liabilities for substantially all of its operating lease commitments based on the present value of committed lease payments as of the date of adoption. The effect on operations and capital adequacy is not expected to be material.

ASU 2016-13

        In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.

        ASU 2016-13 requires credit losses on most financial assets measured at amortized cost and certain other instruments to be measured using an expected credit loss model (referred to as the current expected credit loss (CECL) model). Under this model, entities will estimate credit losses over the entire contractual term of the instrument (considering estimated prepayments, but not expected extensions or modifications unless reasonable expectation of a troubled debt restructuring exists) from the date of initial recognition of that instrument.

        The ASU also replaces the current accounting model for purchased credit impaired loans and debt securities. The allowance for credit losses for purchased financial assets with a more-than insignificant amount of credit deterioration since origination ("PCD assets"), should be determined in a similar manner to other financial assets measured on an amortized cost basis. However, upon initial recognition, the allowance for credit losses is added to the purchase price ("gross up approach") to determine the initial amortized cost basis. The subsequent accounting for PCD financial assets is the same expected loss model described above.

        Further, the ASU made certain targeted amendments to the existing impairment model for available-for-sale (AFS) debt securities. For an AFS debt security for which there is neither the intent nor a more-likely-than-not requirement to sell, an entity will record credit losses as an allowance rather than a write-down of the amortized cost basis.

        Certain incremental disclosures are required. The new standard is effective for fiscal years beginning after December 15, 2019, including interim periods within the fiscal year. For public business entities that are SEC filers, the amendments are effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, with early adoption permitted.

        The Corporation is currently evaluating the impact this ASU will have on its consolidated financial condition or results of operations. Management has developed a committee to address CECL and the committee is currently evaluating options to comply with the ASU in a timely manner.

ASU 2017-08

        In March 2017, the FASB issued ASU 2017-08, Premium Amortization on Purchased Callable Debt Securities.

        ASU 2017-08 shortens the amortization period for premiums on purchased callable debt securities to the earliest call date (i.e., yield-to-earliest call amortization), rather than amortizing over the full contractual term. The ASU does not change the accounting for securities held at a discount.

        The amendments apply to callable debt securities with explicit, noncontingent call features that are callable at fixed prices and on preset dates. If a security may be prepaid based upon prepayments of the underlying loans, not because the issuer exercised a date specific call option, it is excluded from the

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scope of the new standard. However, for instruments with contingent call features, once the contingency is resolved and the security is callable at a fixed price and preset date, the security is within the scope of the amendments. Further, the amendments apply to all premiums on callable debt securities, regardless of how they were generated.

        The amendments require companies to reset the effective yield using the payment terms of the debt security if the call option is not exercised on the earliest call date. If the security has additional future call dates, any excess of the amortized cost basis over the amount repayable by the issuer at the next call date should be amortized to the next call date.

        The amendments are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within those years. Early adoption is permitted, including adoption in an interim period. If an entity early adopts the amendments in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period.

        The Corporation has evaluated the provision of ASU 2017-08 to determine the potential impact of the new standard and has determined that it is not expected to have a significant impact on its consolidated financial condition or results of operations, as the Corporation holds one security that this ASU would impact.

ASU 2017-04

        In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment.

        ASU 2017-04 eliminates Step 2 of the goodwill impairment test. As such, an entity will perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize a goodwill impairment charge for the amount by which the reporting unit's carrying amount exceeds its fair value. If fair value exceeds the carrying amount, no impairment should be recorded. Any loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Impairment losses on goodwill cannot be reversed once recognized.

        An entity may still perform the optional qualitative assessment for a reporting unit to determine if it is more likely than not that goodwill is impaired. However, the ASU eliminates the requirement to perform a qualitative assessment for any reporting unit with a zero or negative carrying amount. Therefore, the same one-step impairment assessment will apply to all reporting units. However, for a reporting unit with a zero or negative carrying amount, the ASU adds a requirement to disclose the amount of goodwill allocated to it and the reportable segment in which it is included.

        For public business entities that are SEC filers, the amendments are effective with their annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017.

        The Corporation has evaluated the provision of ASU 2017-04 to determine the potential impact of the new standard and has determined that it is not expected to have an impact on its consolidated financial condition or results of operations based on the current circumstances.

ASU 2017-07

        In March 2017, the FASB issued ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost.

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        ASU 2017-07 requires that an employer disaggregate the service cost component from the other components of net benefit cost, as follows:

•

Service cost must be presented in the same line item(s) as other employee compensation costs. These costs are generally included within income from continuing operations, but in some cases may be eligible for capitalization, if certain criteria are met.



•

All other components of net benefit cost must be presented in the income statement separately from the service cost component and outside a subtotal of income from operations, if one is presented. These generally include interest cost, actual return on plan assets, amortization of prior service cost included in accumulated other comprehensive income, and gains or losses from changes in the value of the projected benefit obligation or plan assets. If a separate line item is used to present the other components of net benefit cost, it must be appropriately described. If a separate line item is not used, an entity must disclose the line item(s) in the income statement that includes the other components of net benefit cost. The ASU clarifies that these costs are not eligible for capitalization.

        The amendments are effective for public business entities for fiscal years beginning after December 15, 2017, including interim periods within those years. Early adoption is permitted as of the beginning of an annual period.

        The Corporation adopted this ASU on January 1, 2018. The adoption of this ASU did not have an impact on its consolidated financial condition or results of operations based on the current circumstance.

ASU 2017-13

        In September 2017, the FASB issued ASU 2017-13, Revenue Recognition (Topic 605), Revenue from Contracts with Customers (Topic 606), Leases (Topic 840), and Leases (Topic 842).

        ASU 2017-13 adds SEC paragraphs pursuant to an SEC Staff Announcement made at the July 20, 2017 Emerging Issues Task Force (EITF) meeting. The SEC staff announced that it will not object if an entity that qualifies as a public business entity solely because its financial statements or financial information is included in another entity's filing with the SEC adopts ASU 2014-09, Revenue from Contracts with Customers (Topic 606) and ASU 2016-02, Leases (Topic 842) using the effective dates applicable to private entities.

        The amendments represent guidance related to the effective dates of the standards noted above, therefore, the amendments themselves do not have an effective date.

ASU 2018-02

        In February 2018, the FASB issued ASU 2018-02, Income Statement—Reporting Comprehensive Income (Topic 220), Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.

        ASU 2018-02 allows a reclassification from accumulated other comprehensive income (loss) to retained earnings for stranded tax effects resulting from the 2017 Tax Cuts and Jobs Act. Consequently, the amendments eliminate the stranded tax effects resulting from the Tax Cuts and Jobs Act and will improve the usefulness of information reported to financial statement users. However, because the amendments only relate to the reclassification of the income tax effects of the Tax Cuts and Jobs Act, the underlying guidance that requires that the effect of a change in tax laws or rates be included in income from continuing operations is not affected.

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NOTE A—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)

        The amendments in this ASU also require certain disclosures about stranded tax effects.

        The amendments are effective for all entities for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted, including adoption in any interim period, for public business entities for reporting periods for which financial statements have not yet been issued. The amendments should be applied in either the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Cuts and Jobs Act is recognized.

        The Corporation early adopted this ASU. The total adjustment of $1,183,000 is reclassified from Accumulated Other Comprehensive Income (Loss) to Retained Earnings in the Corporation's consolidated statement of condition, as well as, reflected in the consolidated statement of changes in stockholders' equity for the period ended December 31, 2017.

NOTE B—RESTRICTIONS ON CASH AND DUE FROM BANKS

        In return for services obtained through correspondent banks, the Corporation is required to maintain non-interest bearing cash balances in those correspondent banks. At December 31, 2017 and 2016, compensating balances approximated $1,769,000 and $1,203,000, respectively. During 2017 and 2016, average compensating balances approximated $1,992,000 and $1,337,000, respectively. All compensating balances are met by vault cash.

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NOTE C—SECURITIES

        Amortized cost and fair value at December 31, 2017 and 2016, were as follows:

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NOTE C—SECURITIES (Continued)

        The following table shows the Corporation's investments' gross unrealized losses and fair value, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at December 31, 2017 and 2016:

        All mortgage-backed security investments are government sponsored enterprise (GSE) pass-through instruments issued by the Federal National Mortgage Association (FNMA), Government National Mortgage Association (GNMA) or Federal Home Loan Mortgage Corporation (FHLMC), which guarantee the timely payment of principal on these investments.

        At December 31, 2017, sixty-four available for sale U.S. Government and agency securities had unrealized losses that individually did not exceed 5% of amortized cost. Thirty-two of these securities have been in a continuous loss position for 12 months or more. These unrealized losses relate principally to changes in interest rates subsequent to the acquisition of the specific securities.

        At December 31, 2017, fifteen available for sale residential mortgage-backed securities had unrealized losses that individually did not exceed 2% of amortized cost. Three of these securities have

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NOTE C—SECURITIES (Continued)

been in a continuous loss position for 12 months or more. These unrealized losses relate principally to changes in interest rates subsequent to the acquisition of the specific securities.

        At December 31, 2017, fourteen available for sale state and municipal securities had unrealized losses that individually did not exceed 3% of amortized cost. Eight of these securities have been in a continuous loss position for 12 months or more. These unrealized losses relate principally to changes in interest rates subsequent to the acquisition of the specific securities.

        At December 31, 2017, the CRA Mutual Fund had an unrealized loss that did not exceed 1% of amortized cost. This security has been in a continuous loss position for 12 months or more. This unrealized loss relates principally to changes in interest rates subsequent to the acquisition of the specific security.

        At December 31, 2017, nine held to maturity U.S. Government and agency securities had unrealized losses that individually did not exceed 2% of amortized cost. Six of these securities have been in a continuous loss position for 12 months or more. These unrealized losses relate principally to changes in interest rates subsequent to the acquisition of the specific securities.

        At December 31, 2017, twenty-one held to maturity residential mortgage-backed securities had unrealized losses that individually did not exceed 3% of amortized cost. Thirteen of these securities have been in a continuous loss position for 12 months or more. These unrealized losses relate principally to changes in interest rates subsequent to the acquisition of the specific securities.

        In analyzing the issuer's financial condition, management considers industry analysts' reports, financial performance, and projected target prices of investment analysts within a one-year time frame. Based on the above information, management has determined that none of these investments are other-than-temporarily impaired.

        The fair values of securities available for sale (carried at fair value) and held to maturity (carried at amortized cost) are determined by obtaining quoted market prices on nationally recognized securities exchanges (Level 1), or matrix pricing (Level 2), which is a mathematical technique used widely in the industry to value debt securities without relying exclusively on quoted market prices for the specific securities but rather by relying on the security's relationship to other benchmark quoted prices. The Corporation uses independent service providers to provide matrix pricing.

        Management routinely sells securities from its available for sale portfolio in an effort to manage and allocate the portfolio. At December 31, 2017, management had not identified any securities with an unrealized loss that it intends to sell or will be required to sell. In estimating other-than-temporary impairment losses on debt securities, management considers (1) whether management intends to sell the security, or (2) if it is more likely than not that management will be required to sell the security before recovery, or (3) if management does not expect to recover the entire amortized cost basis. In assessing potential other-than-temporary impairment for equity securities, consideration is given to management's intention and ability to hold the securities until recovery of unrealized losses.

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NOTE C—SECURITIES (Continued)

        Amortized cost and fair value at December 31, 2017, by contractual maturity, where applicable, are shown below. Expected maturities will differ from contractual maturities because issuers may have the right to call or prepay with or without penalties.

        The Corporation realized gross gains of $0 during 2017, $26,000 during 2016, and $262,000 during 2015 and gross losses of $0 during 2017 and 2016, and $1,000 during 2015 on sales of securities available for sale.

        At December 31, 2017 and 2016, securities with a carrying value of $157,601,000 and $134,763,000, respectively, were pledged as collateral as required by law on public and trust deposits, repurchase agreements, and for other purposes.

NOTE D—LOANS AND ALLOWANCE FOR LOAN LOSSES

        The Corporation grants commercial, residential, and consumer loans to customers primarily within southcentral Pennsylvania and northern Maryland and the surrounding area. A large portion of the loan portfolio is secured by real estate. Although the Bank has a diversified loan portfolio, its debtors' ability to honor their contracts is influenced by the region's economy.

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NOTE D—LOANS AND ALLOWANCE FOR LOAN LOSSES (Continued)

        The following tables present the classes of the loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Corporation's internal risk rating system as of December 31, 2017 and 2016:

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NOTE D—LOANS AND ALLOWANCE FOR LOAN LOSSES (Continued)

        The following table provides changes in accretable yield for all acquired loans accounted for under ASC 310-30. Loans accounted for under ASC 310-20 are not included in this table.

        Cash flows expected to be collected on acquired loans are estimated quarterly by incorporating several key assumptions similar to the initial estimate of fair value. These key assumptions include probability of default and the amount of actual prepayments after the acquisition date. Prepayments affect the estimated life of the loans and could change the amount of interest income, and possibly principal expected to be collected. In reforecasting future estimated cash flows, credit loss expectations are adjusted as necessary. Improved cash flow expectations for loans or pools are recorded first as a reversal of previously recorded impairment, if any, and then as an increase in prospective yield when all previously recorded impairment has been recaptured. Decreases in expected cash flows are recognized as impairment through a charge to the provision for loan losses and credit to the allowance for loan losses.

        The following table summarizes information relative to impaired loans by loan portfolio class as of December 31, 2017 and 2016:

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NOTE D—LOANS AND ALLOWANCE FOR LOAN LOSSES (Continued)

        The following table summarizes information in regards to average of impaired loans and related interest income by loan portfolio class:

        No additional funds are committed to be advanced in connection with impaired loans.

        If interest on all nonaccrual loans had been accrued at original contract rates, interest income would have increased by $437,000 in 2017, $369,000 in 2016, and $456,000 in 2015.

        The following table presents nonaccrual loans by loan portfolio class as of December 31, 2017 and 2016, the table below excludes $6.9 million in purchase credit impaired loans, net of unamortized fair value adjustments:

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NOTE D—LOANS AND ALLOWANCE FOR LOAN LOSSES (Continued)

        The following table summarizes information relative to troubled debt restructurings by loan portfolio class at December 31, 2017 and 2016:

        All of the Corporation's troubled debt restructured loans are also impaired loans, of which some have resulted in a specific allocation and, subsequently, a charge-off as appropriate. There were no defaulted troubled debt restructured loans as of December 31, 2017 and 2016, however two borrowers advised that further payments were unlikely, therefore they were moved to nonaccrual status in the second quarter of 2017. There were no charge-offs on any of the troubled debt restructured loans for the years ended December 31, 2017 and 2016. One troubled debt restructured loan had a specific allocation in the amount of $60,000 at December 31, 2017. There was no specific allocation on any troubled debt restructured loans for the year ended December 31, 2016. One troubled debt restructured loan paid off during 2017 in the amount of $283,000. One troubled debt restructured loan paid off during 2016 in the amount of $74,000. All other troubled debt restructured loans were current with respect to their associated forbearance agreement, except for one loan which has had periodic late payments. As of December 31, 2017, only one of the loans classified as a troubled debt restructured loan has an active forbearance agreement. The loan was negotiated during 2016. All other forbearance agreements have expired or the loans have paid off.

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NOTE D—LOANS AND ALLOWANCE FOR LOAN LOSSES (Continued)

        The following table summarizes loans whose terms have been modified resulting in troubled debt restructurings during the years ended December 31, 2017 and 2016:

        Consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings are in process at December 31, 2017 and 2016, totaled $848,000 and $471,000, respectively.

        The performance and credit quality of the loan portfolio is also monitored by analyzing the age of the loans receivable as determined by the length of time a recorded payment is past due.

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NOTE D—LOANS AND ALLOWANCE FOR LOAN LOSSES (Continued)

        The following table presents the classes of the loan portfolio summarized by the past due status as of December 31, 2017 and 2016:

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NOTE D—LOANS AND ALLOWANCE FOR LOAN LOSSES (Continued)

        The following table summarizes the allowance for loan losses and recorded investment in loans:

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NOTE D—LOANS AND ALLOWANCE FOR LOAN LOSSES (Continued)

        The Bank has granted loans to certain of its executive officers, directors and their related interests. These loans were made on substantially the same basis, including interest rates and collateral as those prevailing for comparable transactions with other borrowers at the same time. The aggregate amount of these loans was $5,703,000 and $4,578,000 at December 31, 2017 and 2016, respectively. During 2017, $1,612,000 new loans or advances were extended and repayments totaled $487,000. None of these loans were past due, in nonaccrual status, or restructured at December 31, 2017.

NOTE E—PREMISES AND EQUIPMENT

        Premises and equipment at December 31 were as follows:

        Depreciation expense was $1,755,000, $1,455,000 and $1,419,000 for the years ended December 31, 2017, 2016 and 2015, respectively.

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NOTE F—INVESTMENTS IN LOW-INCOME HOUSING PARTNERSHIPS

        ACNB Corporation is a limited partner in three partnerships, whose purpose is to develop, manage and operate residential low-income properties. At December 31, 2017 and 2016, the carrying value of these investments was approximately $2,446,000 and $2,899,000, respectively.

NOTE G—DEPOSITS

        Deposits were comprised of the following as of December 31:

        Scheduled maturities of time certificates of deposit at December 31, 2017, were as follows:

NOTE H—LEASE COMMITMENTS

        Certain branch offices and equipment are leased under agreements which expire at varying dates through 2036. Most leases contain renewal provisions at the Corporation's option. The total rental expense for all operating leases was $642,000, $492,000 and $456,000 for the years ended December 31, 2017, 2016 and 2015, respectively.

        The following is a schedule by year of future minimum rental payments required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year as of December 31:

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NOTE H—LEASE COMMITMENTS (Continued)

        ACNB leases space at several of its owned offices to other unrelated organizations. Total rental income for these properties was $60,000, $8,000 and $27,000 for the years ended December 31, 2017, 2016 and 2015, respectively.

NOTE I—BORROWINGS

        Short-term borrowings and weighted-average interest rates at December 31 are as follows:

        Under an agreement with the FHLB, the Bank has short-term borrowing capacity included within its maximum borrowing capacity. All FHLB advances are collateralized by a security agreement covering qualifying loans and unpledged U.S. Treasury, agency and mortgage-backed securities. In addition, all FHLB advances are secured by the FHLB capital stock owned by the Bank having a par value of $4,194,700 at December 31, 2017. The Corporation also has lines of credit that total $29,000,000 with correspondent banks for overnight federal funds borrowings. There were no advances on these lines at December 31, 2017 and 2016.

        The Corporation enters into agreements under which it sells securities subject to an obligation to repurchase the same or similar securities. Under these arrangements, the Corporation may transfer legal control over the assets but still retain effective control through an agreement that both entitles and obligates the Corporation to repurchase the assets. As a result, these repurchase agreements are accounted for as collateralized financing agreements (i.e., secured borrowings) and not as a sale and subsequent repurchase of securities. The obligation to repurchase the securities is reflected as a liability in the Corporation's consolidated statements of condition, while the securities underlying the repurchase agreements remain in the respective investment securities asset accounts. In other words, there is no offsetting or netting of the investment securities assets with the repurchase agreement liabilities. In addition, as the Corporation does not enter into reverse repurchase agreements, there is no such offsetting to be done with the repurchase agreements.

        The right of setoff for a repurchase agreement resembles a secured borrowing, whereby the collateral would be used to settle the fair value of the repurchase agreement should the Corporation be in default (e.g., fails to make an interest payment to the counterparty). For private institution repurchase agreements, if the private institution counterparty were to default (e.g., declare bankruptcy), the Corporation could cancel the repurchase agreement (i.e., cease payment of principal and interest), and attempt collection on the amount of collateral value in excess of the repurchase agreement fair value. The collateral is held by a third-party financial institution in the counterparty's custodial account. The counterparty has the right to sell or repledge the investment securities. For government entity repurchase agreements, the collateral is held by the Corporation in a segregated custodial account under a tri-party agreement.

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NOTE I—BORROWINGS (Continued)

        The following table presents the short-term borrowings subject to an enforceable master netting arrangement or repurchase agreement as of December 31, 2017 and 2016:

        A summary of long-term debt as of December 31 is as follows:

        The FHLB advances are collateralized by the assets defined in security agreement and FHLB capital stock described previously. The Corporation can borrow a maximum of $674,680,200 from the FHLB, of which $567,440,200 was available at December 31, 2017.

        The loan payable to a local bank has a one-year draw period in which monthly interest-only payments are due on the outstanding principal amount at 4.5% as of December 31, 2017. Commencing June 2018, terms include a fixed rate of 4.5% for the first five years and a variable rate of interest with Prime Rate thereafter to final maturity in June 2028. The principal balance of this note may be prepaid at any time without penalty.

        The trust preferred subordinated debt is comprised of debt securities issued by New Windsor in June 2005 and assumed by ACNB Corporation through the acquisition. New Windsor issued $5,000,000 of 6.39% fixed rate capital securities to institutional investors in a private pooled transaction. The proceeds were transferred to New Windsor as trust preferred subordinated debt under the same terms

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NOTE I—BORROWINGS (Continued)

and conditions. The Corporation then contributed the full amount to the Bank in the form of Tier 1 capital. The Corporation has, through various contractual agreements, fully and unconditionally guaranteed all of the trust obligations with respect to the capital securities.

NOTE J—REGULATORY RESTRICTIONS ON DIVIDENDS

        Dividend payments by the Bank to the Corporation are subject to the Pennsylvania Banking Code, the Federal Deposit Insurance Act, and the regulations of the FDIC, including final rules to implement the Basel III regulatory capital reforms and changes required by the Dodd-Frank Act. Under the Banking Code, no dividends may be paid except from "accumulated net earnings" (generally, retained earnings). The Federal Reserve Board and the FDIC have formal and informal policies which provide that insured banks and bank holding companies should generally pay dividends only out of current operating earnings, with some exceptions. As of December 31, 2017, $16,066,000 of undistributed earnings of the Bank, included in consolidated retained earnings, was available for distribution to the Corporation as dividends without prior regulatory approval. Additionally, dividends paid by the Bank to the Corporation would be prohibited if the effect thereof would cause the Bank's capital to be reduced below applicable minimum capital requirements.

NOTE K—INCOME TAXES

        The components of income tax expense for the years ended December 31, 2017, 2016 and 2015, are as follows:

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NOTE K—INCOME TAXES (Continued)

        Reconciliations of the statutory federal income tax to the income tax expense reported in the consolidated statements of income for the years ended December 31, 2017, 2016 and 2015, are as follows:

        The provision for federal income taxes includes $0, $9,000 and $89,000 of income taxes related to net gains on sales of securities in 2017, 2016 and 2015, respectively. Rehabilitation and low-income housing income tax credits were $287,000, during 2017, 2016 and 2015, respectively. Projected credits are $287,000 in 2018 and 2019, and $876,000 thereafter.

        Components of deferred tax assets and liabilities at December 31 were as follows:

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NOTE K—INCOME TAXES (Continued)

        The Corporation did not have any uncertain tax positions at December 31, 2017 and 2016. The Corporation's policy is to recognize interest and penalties on unrecognized tax benefits in income tax expense in the Consolidated Statements of Income.

        Years that remain open for potential review by the Internal Revenue Service are 2014 through 2017.

        On December 22, 2017, the United States government enacted comprehensive tax legislation, known as the Tax Cuts and Jobs Act (the "Tax Act"). The Tax Act made broad and complex changes to the U.S. tax code, including a reduction in the base corporate tax rate from the prior existing statutory rate, which was 35% for ACNB, to 21%. Based on estimates and current accounting guidance, the Corporation estimated that the Tax Act resulted in a charge against 2017 net income of approximately $1.7 million, due to the write down of ACNB's net deferred tax assets due to the Tax Act's reduction in the base corporate tax rate to 21%. This estimate was based on a review and analysis of the Corporation's net deferred tax assets at December 31, 2017, as well as adjustments to various deferred tax assets and deferred tax liabilities in the fourth quarter, including those accounted for in accumulated other comprehensive income.

NOTE L—FAIR VALUE MEASUREMENTS

        Management uses its best judgment in estimating the fair value of the Corporation's financial instruments; however, there are inherent weaknesses in any estimation technique. Therefore, for substantially all financial instruments, the fair value estimates herein are not necessarily indicative of the amounts the Corporation could have realized in a sales transaction on the dates indicated. The estimated fair value amounts have been measured as of their respective reporting dates and have not been reevaluated or updated for purposes of these consolidated financial statements subsequent to those respective dates. As such, the estimated fair values of these financial instruments subsequent to the respective reporting dates may be different than the amounts reported at each period end.

        Fair value measurement and disclosure guidance defines fair value as the price that would be received to sell the asset or transfer the liability in an orderly transaction (that is, not a forced liquidation or distressed sale) between market participants at the measurement date under current market conditions.

        Fair value measurement and disclosure guidance provides a list of factors that a reporting entity should evaluate to determine whether there has been a significant decrease in the volume and level of activity for the asset or liability in relation to normal market activity for the asset or liability. When the reporting entity concludes there has been a significant decrease in the volume and level of activity for the asset or liability, further analysis of the information from that market is needed and significant adjustments to the related prices may be necessary to estimate fair value in accordance with fair value measurement and disclosure guidance.

        This guidance further clarifies that when there has been a significant decrease in the volume and level of activity for the asset or liability, some transactions may not be orderly. In those situations, the entity must evaluate the weight of the evidence to determine whether the transaction is orderly. The guidance provides a list of circumstances that may indicate that a transaction is not orderly. A transaction price that is not associated with an orderly transaction is given little, if any, weight when estimating fair value.

        Fair value measurement and disclosure guidance establishes a fair value hierarchy that prioritizes the inputs to valuation methods used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and

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the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are as follows:

        Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities.

        Level 2: Quoted prices in markets that are not active, or inputs that are observable, either directly or indirectly, for substantially the full term of the asset or liability.

        Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported with little or no market activity).

        An asset or liability's level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement.

        For assets measured at fair value, the fair value measurements by level within the fair value hierarchy, and the basis of measurement used at December 31, 2017 and 2016, are as follows:

 

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NOTE L—FAIR VALUE MEASUREMENTS (Continued)

        The following table presents additional quantitative information about assets measured at fair value on a nonrecurring basis for which the Corporation has utilized Level 3 inputs to determine fair value:

        The following information should not be interpreted as an estimate of the fair value of the entire Corporation since a fair value calculation is only provided for a limited portion of the Corporation's assets and liabilities. Due to a wide range of valuation techniques and the degree of subjectivity used in making the estimates, comparisons between the Corporation's disclosures and those of other companies may not be meaningful. The following methods and assumptions were used to estimate the fair values of certain Corporation assets and liabilities at December 31, 2017 and 2016:

Cash and Cash Equivalents (Carried at Cost)

        The carrying amounts reported in the consolidated statement of condition for cash and short-term instruments approximate those assets' fair value. U.S. currency is Level 1 and cash equivalents are Level 2.

Securities

        The fair values of securities available for sale (carried at fair value) and held to maturity (carried at amortized cost) are determined by obtaining quoted market prices on nationally recognized securities exchanges (Level 1), or matrix pricing (Level 2), which is a mathematical technique used widely in the industry to value debt securities without relying exclusively on quoted market prices for the specific security but rather by relying on the security's relationship to other benchmark quoted prices. The Corporation uses an independent service provider to provide matrix pricing, and uses the valuation of another provider to compare for reasonableness.

Loans Held for Sale (Carried at Lower of Cost or Fair Value)

        The fair values of mortgage loans held for sale are determined based on amounts to be received at settlement by establishing the respective buyer requirement or market interest rates.

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Loans (Carried at Cost)

        The fair values of non-impaired loans are estimated using discounted cash flow analyses, as well as using market rates at the balance sheet date that reflect the credit and interest rate risk inherent in the loans. Projected future cash flows are calculated based upon contractual maturity or call dates, projected repayments, and prepayments of principal. Generally, for variable rate loans that reprice frequently and with no significant change in credit risk, fair values are based on carrying values.

Impaired Loans (Generally Carried at Fair Value)

        Loans for which the Corporation has measured impairment are generally based on the fair value of the loan's collateral. Fair value is generally determined based upon independent third-party appraisals of the properties, or discounted cash flows based upon the expected proceeds. These assets are included as Level 3 fair values, based upon the lowest level of input that is significant to the fair value measurements. The fair value consists of the loan balances less the valuation allowance and/or charge-offs.

Foreclosed Assets Held for Resale

        The fair value of real estate acquired through foreclosure is based on independent third-party appraisals of the properties. These assets are included as Level 3 fair values, based upon appraisals that consider the sales prices of similar properties in the proximate vicinity.

        It is the policy of the Corporation to have the initial market value of a foreclosed asset held for resale determined by an independent third-party valuation. If the Corporation already has a valid appraisal on file for the property and that appraisal has been completed within the previous 12 months, another appraisal shall not be required when the Corporation acquires ownership of that real estate. Further, the Corporation shall update the market value of each foreclosed asset with an independent third-party valuation at least every 18 months, or more frequently if management believes that there is an indication that the fair value has declined. These valuations may be adjusted downward to account for specialized use of the property, change in the condition of the real estate, change in local market and economic conditions, and other specific factors involving the collateral.

Restricted Investment in Bank Stock (Carried at Cost)

        The carrying amount of required and restricted investment in correspondent bank stock approximates fair value, and considers the limited marketability of such securities.

Accrued Interest Receivable and Payable (Carried at Cost)

        The carrying amounts of accrued interest receivable and accrued interest payable approximate their fair value.

Deposits (Carried at Cost)

        The fair values disclosed for demand deposits (e.g., interest and non-interest checking, savings, and money market accounts) are, by definition, equal to the amount payable on demand at the reporting date (e.g., their carrying amounts). Fair values for fixed-rate certificates of deposit are estimated using a discounted cash flow calculation that applies market interest rates currently being offered in the market on certificates to a schedule of aggregated expected monthly maturities on time deposits.

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NOTE L—FAIR VALUE MEASUREMENTS (Continued)

Short-Term Borrowings (Carried at Cost)

        The carrying amounts of short-term borrowings approximate their fair values.

Long-Term Borrowings (Carried at Cost)

        The fair values of long-term borrowings are estimated using discounted cash flow analysis, based on quoted prices for new borrowings with similar credit risk characteristics, terms, and remaining maturity. The prices obtained from this active market represent a market value that is deemed to represent the transfer price if the liability were assumed by a third party. The fair value of the trust preferred subordinated debt, included in long-term borrowings, was determined based upon an estimated fair value from an independent brokerage firm.

Off-Balance Sheet Credit-Related Instruments

        The fair values for the Corporation's off-balance sheet financial instruments (specifically, lending commitments and letters of credit) are based on fees currently charged in the market to enter into similar agreements, taking into account the remaining terms of the agreements and the counterparties' credit standing.

        The following presents the carrying amount, fair value, and placement in the fair value hierarchy of the Corporation's financial instruments at December 31, 2017 and 2016:

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NOTE L—FAIR VALUE MEASUREMENTS (Continued)

NOTE M—RETIREMENT PLANS

        The Corporation's banking subsidiary has a non-contributory, defined benefit pension plan. Retirement benefits are a function of both years of service and compensation. The funding policy is to contribute annually the amount that is sufficient to meet the minimum funding requirements set forth in the Employee Retirement Income Security Act.

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NOTE M—RETIREMENT PLANS (Continued)

        A measurement date of December 31 has been used for the fiscal years ended December 31, 2017 and 2016.

        The estimated costs that will be amortized from accumulated other comprehensive loss into net periodic pension cost during the next fiscal year are as follows:

        The accumulated benefit obligation totaled $30,228,000 and $27,508,000 at December 31, 2017 and 2016, respectively.

        For the years ended December 31, 2017 and 2016 the mortality assumptions were derived using the mortality rates from RP-2006 (underlying baseline table from SOA RP-2014 study based on experience data for private pension plans of 2006, the central year of experience data 2004-2008).

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NOTE M—RETIREMENT PLANS (Continued)

        The components of net periodic benefit costs (income) related to the non-contributory, defined benefit pension plan for the years ended December 31 are as follows:

        For the years ended December 31, 2017, 2016 and 2015, the assumptions used to determine the benefit obligation are as follows:

        For the years ended December 31, 2017, 2016 and 2015, the assumptions used to determine the net periodic benefit cost (income) are as follows:

        The Corporation's pension plan weighted-average assets' allocations at December 31, 2017 and 2016, are as follows:

        The Corporation's overall investment strategy is to achieve a mix of investments to meet the long-term rate of return assumption and near-term pension obligations with a diversification of assets types, fund strategies and fund managers. The mix of investments is adjusted periodically by retaining an advisory firm to recommend appropriate allocations after reviewing the Corporation's risk tolerance on contribution levels, funded status and plan expense, and any applicable regulatory requirements. The

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NOTE M—RETIREMENT PLANS (Continued)

weighted-average assets' allocation in the above table represents the Corporation's conclusion on the appropriate mix of investments. The specific investment vehicles are institutional separate accounts from a variety of fund managers which are regularly reviewed by the Corporation for acceptable performance.

        Equity securities included Corporation common stock in amounts of $2,114,000, or 5% of total plan assets, and $2,175,000, or 6% of total plan assets, at December 31, 2017 and 2016, respectively.

        Fair value measurements at December 31, 2017, are as follows:

        Fair value measurements at December 31, 2016, are as follows:

        It has not yet been determined the amount that the Bank may contribute to the Plan in 2018. The Corporation reduced the future benefit accruals for the defined benefit pension plan effective January 1, 2010, in order to manage total benefit expense. The new formula is the earned benefit as of December 31, 2009, plus 0.75% of a participant's average monthly pay multiplied by years of benefit service earned on and after January 1, 2010, but not more than 25 years. The benefit formula percentage and maximum years of benefit service were both reduced. Effective April 1, 2012, no inactive or former participant in the Plan is eligible to again participate in the plan, and no employee hired after March 31, 2012, is eligible to participate in the Plan. As of the last annual census, ACNB Bank had a combined 353 active, vested terminated, and retired persons in the Plan.

        Based on current data and assumptions, the following benefit payments, which reflect expected future service, as appropriate, are:

        The Corporation's banking subsidiary maintains a 401(k) plan for the benefit of eligible employees. Employees may contribute up to 100% of their compensation subject to certain limits based on federal tax laws. The Bank makes matching contributions up to 100% of the first 4% of an employee's compensation contributed to the plan. Matching contributions vest immediately to the employee. Bank contributions to and expenses for the plan were $626,000, $541,000 and $547,000 for 2017, 2016 and 2015, respectively.

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NOTE M—RETIREMENT PLANS (Continued)

        RIG has a similar but separate 401(k) plan with the match of 6% for non-highly compensated employees and 3% match for highly compensated employees. RIG's contributions to and expenses for the plan were $86,000, $83,000 and $74,000 for 2017, 2016 and 2015, respectively.

        The Corporation's banking subsidiary maintains nonqualified compensation plans for selected senior officers. The estimated present value of future benefits is accrued over the period from the effective date of the agreements until the expected retirement dates of the individuals. The balance accrued for these plans included in other liabilities as of December 31, 2017 and 2016, totaled $2,803,000 and $2,550,000, respectively. The annual expense included in salaries and benefits expense totaled $279,000, $383,000 and $360,000 during the years ended December 31, 2017, 2016 and 2015, respectively. To fund the benefits under these plans, the Bank is the owner of single premium life insurance policies on participants in the nonqualified retirement plans.

NOTE N—STOCKHOLDERS' EQUITY AND REGULATORY MATTERS

        In January 2011, the Corporation offered stockholders the opportunity to participate in the ACNB Corporation Dividend Reinvestment and Stock Purchase Plan. The plan provides registered holders of ACNB Corporation common stock with a convenient way to purchase additional shares of common stock by permitting participants in the plan to automatically reinvest cash dividends on all or a portion of the shares owned and to make quarterly voluntary cash payments under the terms of the plan. Participation in the plan is voluntary, and there are eligibility requirements to participate in the plan. During 2017, 14,967 shares were issued under this plan with proceeds in the amount of $362,000. During 2016, 16,979 shares were issued under this plan with proceeds in the amount of $437,000. During 2015, 18,401 shares were issued under this plan with proceeds in the amount of $499,000. Proceeds are used for general corporate purposes.

        On May 5, 2009, stockholders approved and ratified the ACNB Corporation 2009 Restricted Stock Plan, which awards shall not exceed, in the aggregate, 200,000 shares of common stock. The plan is available to employees and directors of the Bank to advance the best interests of ACNB Corporation and its shareholders. The plan provides those persons who have responsibility for its growth with additional incentive by allowing them to acquire an ownership in ACNB Corporation and thereby encouraging them to contribute to the success of the Corporation. To date, 19,301 shares were issued under this plan.

        The Corporation and the Bank are subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet the minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Corporation's consolidated financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Corporation and the Bank must meet specific capital guidelines that involve quantitative measures of their assets, liabilities and certain off-balance sheet items as calculated under regulatory accounting practices. The capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings, and other factors.

        Quantitative measures established by regulation to ensure capital adequacy require the Corporation and the Bank to maintain minimum amounts and ratios (set forth below) of total and Tier 1 capital to average assets. The federal banking agencies issued final rules to implement the Basel III regulatory capital reforms and changes required by the Dodd-Frank Act. The phase-in period for community banking organizations began January 1, 2015, while larger institutions (generally those with

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NOTE N—STOCKHOLDERS' EQUITY AND REGULATORY MATTERS (Continued)

assets of $250 billion or more) began compliance effective January 1, 2014. The final rules call for the following capital requirements:

•

a minimum ratio of common Tier 1 capital to risk-weighted assets of 4.5%;



•

a minimum ratio of Tier 1 capital to risk-weighted assets of 6.0%;



•

a minimum ratio of total capital to risk-weighted assets of 8.0%; and,



•

a minimum leverage ratio of 4.0%.

        In addition, the final rules establish a common equity Tier 1 capital conservation buffer of 2.5% of risk-weighted assets applicable to all banking organizations. If a banking organization fails to hold capital above the minimum capital ratios and the capital conservation buffer, it will be subject to certain restrictions on capital distributions and discretionary bonus payments. The 2.5% at 0.625% per year phase-in period for the capital conservation and countercyclical capital buffers for all banking organizations began on January 1, 2016.

        Management believes, as of December 31, 2017, that the Corporation and the Bank meet all capital adequacy requirements to which they are subject.

        As of December 31, 2017, the most recent notification from the federal banking regulators categorized the Bank as "well capitalized" under the regulatory framework for prompt corrective action. There are no subsequent conditions or events that management believes have changed the Bank's category.

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NOTE N—STOCKHOLDERS' EQUITY AND REGULATORY MATTERS (Continued)

        The actual and required capital amounts and ratios were as follows:

NOTE O—FINANCIAL INSTRUMENTS WITH OFF-BALANCE SHEET RISK

        The Corporation is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments consist primarily of commitments to extend credit (typically mortgages and commercial loans) and, to a lesser extent, standby letters of credit. These instruments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized on the consolidated balance sheet.

        The Corporation's exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit and standby letters of credit is represented by

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NOTE O—FINANCIAL INSTRUMENTS WITH OFF-BALANCE SHEET RISK (Continued)

the contractual amount of those instruments. The Corporation uses the same credit policies in making commitments and conditional obligations as it does for on balance sheet instruments. The Corporation does not anticipate any material losses from these commitments.

        Commitments to extend credit, including commitments to grant loans and unfunded commitments under lines of credit, are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The Corporation evaluates each customer's creditworthiness on a case-by-case basis. The amount of collateral obtained, if deemed necessary by the Corporation upon extensions of credit, is based on management's credit evaluation of the customer. Collateral held varies but may include accounts receivable, inventory, property and equipment and income-producing commercial properties. On loans secured by real estate, the Corporation generally requires loan to value ratios of no greater than 80%.

        Standby letters of credit are conditional commitments issued by the Corporation to guarantee the performance of a customer to a third party. Those guarantees are primarily issued to support public and private borrowing arrangements and similar transactions. The terms of the letters of credit vary and may have renewal features. The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loans to customers. The Corporation generally holds collateral and/or personal guarantees supporting those commitments for which collateral is deemed necessary. Management believes that the proceeds obtained through a liquidation of such collateral and the enforcement of guarantees would be sufficient to cover the maximum potential amount of future payments required under the corresponding guarantees. The current amount of the liability as of December 31, 2017 and 2016, for guarantees under standby letters of credit issued is not material.

        In 2016, ACNB Corporation executed a guaranty for a note related to a $500,000 commercial line of credit from a local bank, with normal terms and conditions for such a line, for Russell Insurance Group, Inc., the borrower and a wholly-owned subsidiary of ACNB Corporation. The commercial line of credit is for general working capital needs should they arise by the borrower. No liability is recorded for the guarantor's obligation as the guarantor would have full recourse from all assets of its wholly-owned subsidiary. No draws were taken on this commercial line of credit since its inception.

        The Corporation has not been required to perform on any financial guarantees, and has not incurred any losses on its commitments, during the past three years.

        A summary of the Corporation's commitments at December 31 were as follows:

NOTE P—CONTINGENCIES

        The Corporation is subject to claims and lawsuits which arise primarily in the ordinary course of business. Based on information presently available and advice received from legal counsel representing the Corporation in connection with any such claims and lawsuits, it is the opinion of management that the disposition or ultimate determination of any such claims and lawsuits will not have a material adverse effect on the consolidated financial position, consolidated results of operations or liquidity of the Corporation.

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NOTE Q—ACNB CORPORATION (PARENT COMPANY ONLY) FINANCIAL INFORMATION

STATEMENTS OF CONDITION

STATEMENTS OF INCOME AND COMPREHENSIVE INCOME

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NOTE Q—ACNB CORPORATION (PARENT COMPANY ONLY) FINANCIAL INFORMATION (Continued)

STATEMENTS OF CASH FLOWS

NOTE R—GOODWILL AND OTHER INTANGIBLES

        On January 5, 2005, ACNB Corporation completed the acquisition of Russell Insurance Group, Inc. (RIG) and RIG began to operate as a separate subsidiary of ACNB Corporation. In accordance with the terms of the acquisition, there was contingent consideration associated with this transaction of up to $3,000,000, payable in 2008 subject to performance criteria for the three-year period subsequent to the acquisition. Due to performance at a higher level than the performance criteria, the liability for this consideration was recorded at December 31, 2006, with a related increase in goodwill. Payment was made in the second quarter of 2008 after it was ascertained that the performance criteria had been met for the full three-year period; after which, the total aggregate purchase price was $8,663,000.

        On July 1, 2017, ACNB completed its acquisition of New Windsor Bancorp Inc. (New Windsor) of Taneytown, Maryland. The acquisition of New Windsor resulted in goodwill of approximately $13,272,000 and generated $2,418,000 in core deposit intangibles.

        Goodwill represents the excess of the cost of an acquisition over the fair value of the net assets acquired. Other intangible assets represent purchased assets that lack physical substance but can be distinguished from goodwill because of contractual or other legal rights. Intangible assets that have finite lives, such as core deposit intangibles, customer relationship intangibles and renewal lists, are amortized over their estimated useful lives and subject to periodic impairment testing. Core deposit

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NOTE R—GOODWILL AND OTHER INTANGIBLES (Continued)

intangibles are primarily amortized over ten years using accelerated methods. Customer renewal lists are amortized over their estimated useful lives which range from eight to thirteen years.

        Combining goodwill resulting from this transaction with existing goodwill from the 2005 RIG purchase of $6,308,000, total goodwill included in the Corporation's consolidated statement of condition is $19,580,000. Goodwill is not deductible for federal income tax purposes. Goodwill, which has an indefinite useful life, is evaluated for impairment annually and is evaluated for impairment more frequently if events and circumstances indicate that the asset might be impaired.

        The carrying value and accumulated amortization of the intangible assets (RIG customer lists and New Windsor core deposit intangibles) are as follows:

        Amortization of the intangible assets for the five years subsequent to December 31, 2017, is expected to be as follows:

NOTE S—SEGMENT AND RELATED INFORMATION

        The Corporation has two reporting segments, the Bank and RIG. RIG is managed separately from the banking segment, which includes the Bank and related financial services that the Corporation offers through its banking subsidiary. RIG offers a broad range of property and casualty, life and health insurance to both commercial and individual clients.

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NOTE S—SEGMENT AND RELATED INFORMATION (Continued)

        Segment information for 2017, 2016 and 2015 is as follows:

NOTE T—NEW WINDSOR ACQUISITION

        On July 1, 2017, ACNB completed its acquisition of New Windsor Bancorp Inc. (New Windsor) of Taneytown, Maryland. New Windsor was a locally owned and managed institution with seven locations in north central Maryland that complemented, enhanced and expanded ACNB's physical presence in north central Maryland. ACNB transacted the acquisition to enhance its competitive strategic position, potential prospective business opportunities, operations, management, prospective financial condition, future earnings and business prospects. Specifically, ACNB believes that the acquisition will enhance its business opportunities in Northern Maryland due to the combined company having a greater market share, market presence and the ability to offer more diverse (i.e. Trust Services) and more profitable products, as well as a broader based and geographically diversified branch system to enhance deposit collection and potentially improve funding costs. The fair value of total assets acquired as a result of the acquisition totaled $319.8 million, loans totaled $263.5 million and deposits totaled $293.3 million. Goodwill recorded in the acquisition was $13.3 million. In accordance with the terms of the Reorganization Agreement, dated November 21, 2016, as amended, New Windsor shareholders received, in aggregate, $4.5 million in cash and 938,360 shares or approximately 13% of the post transaction outstanding shares of the Corporation's common stock. The transaction was valued at $33.3 million based on the Corporation's June 30, 2017 closing price of $30.50 as quoted on NASDAQ. The results of the combined entity's operations are included in the Corporation's Consolidated Financial Statements from the date of acquisition.

        The acquisition of New Windsor is being accounted for as a business combination using the acquisition method of accounting and, accordingly, assets acquired, liabilities assumed, and consideration paid were recorded at estimated fair values on the acquisition date. Fair values are preliminary and subject to refinement for up to one year after the closing date of the acquisition.

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NOTE T—NEW WINDSOR ACQUISITION (Continued)

        The following table summarizes the consideration paid for New Windsor and the fair value of assets acquired and liabilities assumed as of the acquisition date:

Purchase Price Consideration in Common Stock

 

        Pursuant to the accounting requirements, the Corporation assigned a fair value to the assets acquired and liabilities assumed of New Windsor. ASC 820 defines fair value as "the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date."

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NOTE T—NEW WINDSOR ACQUISITION (Continued)

        The calculation of goodwill is subject to change for up to one year after the date of acquisition as additional information relative to the closing date estimates and uncertainties become available. Goodwill and core deposit intangibles are allocated to the banking business segment.

        Fair values of the major categories of assets acquired and liabilities assumed were determined as follows:

Investment securities available-for-sale

        The estimated fair values of the investment securities available for sale, primarily comprised of U.S. Government agency mortgage-backed securities, U.S. government agencies and municipal bonds, were determined using Level 2 inputs in the fair value hierarchy. The fair values were determined using independent pricing services. The Corporation's independent pricing service utilized matrix pricing, which is a mathematical technique used widely in the industry to value debt securities without relying exclusively on quoted market prices for the specific security but rather relying on the security's relationship to other benchmark quoted prices. Management reviewed the data and assumptions used in pricing the securities. A fair value premium of $361,000 was recorded and will be amortized over the estimated life of the investments using the interest rate method.

Loans

        Acquired loans (impaired and non-impaired) are initially recorded at their acquisition-date fair values using Level 3 inputs. Fair values are based on a discounted cash flow methodology that involves assumptions and judgments as to credit risk, expected life time losses, environmental factors, collateral values, discount rates, expected payments and expected prepayments. Specifically, the Corporation has prepared three separate loan fair value adjustments that it believed a market participant might employ in estimating the entire fair value adjustment necessary under ASC 820-10 for the acquired loan portfolio. The three-separate fair valuation methodology employed are: 1) an interest rate loan fair value adjustment (analysis available at request of the Corporation), 2) a general credit fair value adjustment (analysis available at request of the Corporation), and 3) a specific credit fair value adjustment for purchased credit impaired loans subject to ASC 310-30 procedures. The acquired loans were recorded at fair value at the acquisition date without carryover of New Windsor's previously established allowance for loan losses. The fair value of the financial assets acquired included loans receivable with a gross amortized cost basis of $272,646,000. The table below illustrates the fair value adjustments made to the amortized cost basis in order to present a fair value of the loans acquired. The credit adjustment on purchased credit impaired loans is derived in accordance with ASC 310-30 and represents the portion of the loan balances that has been deemed uncollectible based on the Corporation's expectations of future cash flows for each respective loan.

        For loans acquired without evidence of credit quality deterioration, ACNB prepared the interest rate loan fair value and credit fair value adjustments. Loans were grouped into homogeneous pools by characteristics such as loan type, term, collateral and rate. Market rates for similar loans were obtained

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NOTE T—NEW WINDSOR ACQUISITION (Continued)

from various internal and external data sources and reviewed by management for reasonableness. The average of these rates was used as the fair value interest rate a market participant would utilize. A present value approach was utilized to calculate the interest rate fair value discount of $731,000.

        Additionally for loans acquired without credit deterioration, a credit fair value adjustment was calculated using a two-part credit fair value analysis: 1) expected lifetime credit migration losses; and 2) estimated fair value adjustment for certain qualitative factors. The expected lifetime losses were calculated using historical losses observed at the Bank, NWSB and peer banks. ACNB also estimated an environmental factor to apply to each loan type. The environmental factor represents potential discount which may arise due to general credit and economic factors. A credit fair value discount of $4.5 million was determined. Both the interest rate and credit fair value adjustments relate to loans acquired with evidence of credit quality deterioration will be substantially recognized as interest income on a level yield amortization method over the expected life of the loans.

        The following table presents the acquired purchased credit impaired loans receivable at the Acquisition Date:

Premises and Equipment

        The Corporation acquired seven branches from New Windsor. The fair value of New Windsor's premises, including land, buildings, and improvements, was determined based upon independent third-party appraisals and other data in the market in which the premises are located. The Corporation prepared an internal analysis to compare the lease contract obligations to comparable market rental rates. The Corporation believed that the leased contract rates were in a reasonable range of market rental rates and concluded that no fair market value adjustment related to leasehold interest was necessary.

Core Deposit Intangible

        The fair value of the core deposit intangible was determined based on a discounted cash flow analysis using a discount rate commensurate with market participants. To calculate cash flows, deposit account servicing costs (net of deposit fee income) and interest expense on deposits were compared to the cost of alternative funding sources available through national brokered CD offering rates. The projected cash flows were developed using projected deposit attrition rates. The core deposit intangible will be amortized over ten years using the sum-of-years digits method.

Time Deposits

        The fair value adjustment for time deposits represents a discount from the value of the contractual repayments of fixed-maturity deposits using prevailing market interest rates for similar-term time deposits. The time deposit discount of approximately $847,500 is being amortized into income on a level yield amortization method over the contractual life of the deposits.

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NOTE T—NEW WINDSOR ACQUISITION (Continued)

Long-term Borrowings

        The Corporation assumed a trust preferred subordinated debt in connection with the acquisition. The fair value of the trust preferred subordinated debt was determined based upon an estimated fair value from an independent brokerage firm. The trust preferred capital note was valued at discount of $312,500, which is being amortized into income on a level yield amortization method based upon the assumed market rate, and the term of the trust preferred subordinated debt instrument.

        The following table presents certain pro forma information as if New Windsor had been acquired on December 31, 2016. These results combine the historical results of the Corporation in the Corporation's Consolidated Statements of Income and, while certain adjustments were made for the estimated impact of certain fair value adjustments and other acquisition-related activity, they are not indicative of what would have occurred had the acquisition taken place on December 31, 2016. In particular, no adjustments have been made to eliminate the amount of New Windor's provision for loan losses that would not have been necessary had the acquired loans been recorded at fair value as of December 31, 2016. The Corporation expects to achieve further operating cost savings and other business synergies as a result of the acquisition which are not reflected in the pro forma amounts below:

        Acquisition-related expenses associated with the acquisition of New Windsor were $4,728,000 and $472,000 for the year ended December 31, 2017 and 2016, respectively. Such costs include legal and accounting fees, lease and contract termination expenses, system conversion, operations integration, and employee severances, which have been expensed as incurred.

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Note U—QUARTERLY RESULTS OF OPERATIONS (UNAUDITED)

        Selected quarterly information for the years ended December 31, 2017 and 2016, is as follows:

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ITEM 9—CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

        None.

ITEM 9A—CONTROLS AND PROCEDURES

EVALUATION OF DISCLOSURE CONTROLS AND PROCEDURES

        The Corporation carried out an evaluation, under the supervision and with the participation of its management, including the Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of its disclosure controls and procedures pursuant to Exchange Act Rule 13a-15. Based upon that evaluation, the Chief Executive Officer and Chief Financial Officer concluded that the Corporation's disclosure controls and procedures are effective in timely alerting them to material information relating to the Corporation (including its consolidated subsidiaries) required to be included in periodic SEC filings.

        Based on the evaluation of the effectiveness of the design and operation of the disclosure controls and procedures, the Chief Executive Officer and Chief Financial Officer concluded that the Corporation's disclosure controls and procedures were effective as of December 31, 2017. The Corporation believes that the accompanying consolidated financial statements fairly present the financial condition and results of operations for the fiscal years presented in this report on Form 10-K.

CHANGES IN INTERNAL CONTROLS OVER FINANCIAL REPORTING

        There were no changes made in the Corporation's internal control over financial reporting in connection with the fourth quarter evaluation that have materially affected, or are reasonably likely to materially affect, the internal control over financial reporting.

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MANAGEMENT'S REPORT ON INTERNAL CONTROL OVER FINANCIAL REPORTING

        ACNB Corporation (ACNB) is responsible for the preparation, integrity, and fair presentation of the consolidated financial statements included in this annual report. The consolidated financial statements and notes included in this annual report have been prepared in conformity with United States generally accepted accounting principles and, as such, include some amounts that are based on management's best estimates and judgments.

        ACNB's management is responsible for establishing and maintaining effective internal control over financial reporting. The system of internal control over financial reporting, as it relates to the consolidated financial statements, is evaluated for effectiveness by management and tested for reliability through a program of internal audits and management testing and review. Actions are taken to correct potential deficiencies as they are identified. Any system of internal control, no matter how well designed, has inherent limitations, including the possibility that a control can be circumvented or overridden and misstatements due to error or fraud may occur and not be detected. Also, because of changes in conditions, internal control effectiveness may vary over time. Accordingly, even an effective system of internal control will provide only reasonable assurance with respect to financial statement preparation.

        The Board of Directors of ACNB, through its Audit Committee, meets regularly with management, internal auditors, and the independent registered public accounting firm. The Audit Committee provides oversight to ACNB by reviewing audit plans and results, and evaluates management's actions for internal control, accounting and financial reporting matters. The internal auditors and independent registered public accounting firm have direct and confidential access to the Audit Committee to discuss the results of their examinations.

        Management assessed the effectiveness of ACNB's internal control over financial reporting as of December 31, 2017. In making this assessment, it used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in its Internal Control—Integrated Framework (2013). Based on our assessment, management concluded that as of December 31, 2017, ACNB's internal control over financial reporting is effective and meets the criteria of the Internal Control—Integrated Framework (2013).

        ACNB's independent registered public accounting firm, BDO USA, LLP, has issued an attestation report on ACNB's internal control over financial reporting. This report appears on the following page.

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Stockholders and Board of Directors
ACNB Corporation
Gettysburg, Pennsylvania

Opinion on Internal Control over Financial Reporting

        We have audited ACNB Corporation's (the Corporation) internal control over financial reporting as of December 31, 2017, based on criteria established in Internal Control—Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (the COSO criteria). In our opinion, the Corporation maintained, in all material respects, effective internal control over financial reporting as of December 31, 2017, based on the COSO criteria.

        We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated statements of condition of the Corporation and subsidiaries as of December 31, 2017 and 2016, the related consolidated statements of income, comprehensive income, stockholders' equity, and cash flows for each of the three years in the period ended December 31, 2017, and the related notes and our report dated March 9, 2018 expressed an unqualified opinion.

Basis for Opinion

        The Corporation's management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management's Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Corporation's internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Corporation in accordance with U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

        We conducted our audits of internal control over financial reporting in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audits included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control over Financial Reporting

        A company's internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company's internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company's assets that could have a material effect on the financial statements.

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        Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ BDO USA, LLP

Harrisburg, Pennsylvania
March 9, 2018

ITEM 9B—OTHER INFORMATION

        None.

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PART III

ITEM 10—DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

        The information required by this Item 10, relating to directors, executive officers, and control persons, is set forth in sections "Information as to Nominees and Directors", "Executive Officers of ACNB Corporation and/or Subsidiary", "Meetings and Committees of the Board of Directors", "Audit Committee Report" and "Section 16(a) Beneficial Ownership Reporting Compliance" of ACNB Corporation's definitive Proxy Statement to be used in connection with the 2018 Annual Meeting of Shareholders, which pages are incorporated herein by reference.

        The Corporation first adopted a Code of Ethics that applies to directors, officers and employees of the Corporation and its subsidiaries in 2003. A copy of the Code of Ethics, as revised and approved by the Corporation's Board of Directors on February 26, 2013, and as reaffirmed on February 27, 2018, is available under the Corporate Governance Documents section of the Investor Relations page of ACNB Bank's website at www.acnb.com. A request for the Corporation's Code of Ethics can be made either in writing to Lynda L. Glass, Executive Vice President/Secretary & Chief Governance Officer, ACNB Corporation, 16 Lincoln Square, P.O. Box 3129, Gettysburg, Pennsylvania 17325 or by telephone at 717-334-3161.

        There have been no material changes to the procedures by which stockholders may recommend nominees to the Corporation's Board of Directors.

ITEM 11—EXECUTIVE COMPENSATION

        Incorporated by reference in response to this Item 11 is the information appearing under the headings "Compensation and Plan Information", "Executive Compensation and Employee Benefits", "Potential Payments Upon Termination or Change In Control", "Compensation Committee Report" and "Compensation Committee Interlocks and Insider Participation" in ACNB Corporation's 2018 definitive Proxy Statement.

ITEM 12—SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS

        Incorporated by reference in response to this Item 12 is the information appearing under the heading "Share Ownership" in ACNB Corporation's 2018 definitive Proxy Statement.

        The following table provides information about shares of the Corporation's stock that may be issued under existing equity compensation plans as of December 31, 2017:

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ITEM 13—CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS AND DIRECTOR INDEPENDENCE

        Incorporated by reference in response to this Item 13 is the information appearing under the headings "Transactions with Directors and Executive Officers" and "Governance of the Corporation" in ACNB Corporation's 2018 definitive Proxy Statement.

ITEM 14—PRINCIPAL ACCOUNTANT FEES AND SERVICES

        Incorporated by reference in response to this Item 14 is the information appearing under the heading "Independent Auditors" in ACNB Corporation's 2018 definitive Proxy Statement.

PART IV

ITEM 15—EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

(a)

1. FINANCIAL STATEMENTS

        The following financial statements are filed as part of this report:

•

Report of Independent Registered Public Accounting Firm



•

Consolidated Statements of Condition



•

Consolidated Statements of Income



•

Consolidated Statements of Comprehensive Income



•

Consolidated Statements of Changes in Stockholders' Equity



•

Consolidated Statements of Cash Flows



•

Notes to Consolidated Financial Statements

2.

FINANCIAL STATEMENT SCHEDULES

        Financial statement schedules are omitted because the required information is either not applicable, not required, or is shown in the respective consolidated financial statements or in the notes thereto.

(b)

EXHIBITS

        The following exhibits are included in this report:

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ITEM 16—FORM 10-K SUMMARY

        None.

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SIGNATURES

        Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

        Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed on March 9, 2018, by the following persons in the capacities indicated.

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