CALCULATION OF REGISTRATION FEE

Filed Pursuant to Rule 424(b)(2)
Registration Statement No. 333-227244

Prospectus Supplement to Prospectus dated September 7, 2018.

¥53,400,000,000

Aflac Incorporated

¥29,300,000,000 1.159% Senior Notes due 2030

¥15,200,000,000 1.488% Senior Notes due 2033

¥8,900,000,000 1.750% Senior Notes due 2038

This is an offering by Aflac Incorporated of ¥29,300,000,000 principal amount of its 1.159% Senior Notes due 2030 (the “2030 notes”), ¥15,200,000,000 principal amount of its 1.488% Senior Notes due 2033 (the “2033 notes”) and ¥8,900,000,000 principal amount of its 1.750% Senior Notes due 2038 (the “2038 notes” and, together with the 2030 notes and the 2033 notes, the “notes”). We will pay interest on the notes semi-annually in arrears on each April 18 and October 18, beginning on April 18, 2019. The 2030 notes will mature on October 18, 2030, the 2033 notes will mature on October 18, 2033, and the 2038 notes will mature on October 18, 2038.

The notes will not be redeemable prior to maturity unless certain events occur involving United States taxation, as described under the caption “Description of the Notes—Tax Redemption” in this prospectus supplement. The notes will be our general unsecured obligations and will rank equally in right of payment with any of our existing and future unsecured senior indebtedness. The notes will be issued only in denominations of ¥100,000,000 and integral multiples of ¥10,000,000 in excess thereof.

The notes will not be listed on any securities exchange. Currently, there is no public market for the notes.

See “Risk Factors” beginning on page S-4 of this prospectus supplement, page 5 of the accompanying prospectus and “Item 1A. Risk Factors” on page 14 of our Annual Report on Form 10-K for the year ended December 31, 2017, on page 96 of our Quarterly Report on Form 10-Q for the quarter ended June 30, 2018 and on page 90 of our Quarterly Report on Form 10-Q for the quarter ended March 31, 2018 to read about factors you should consider before investing in the notes.

Neither the Securities and Exchange Commission (the “SEC”) nor any other regulatory body has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

The underwriters expect to deliver the notes to investors in book-entry form only through Clearstream Banking, S.A, or Euroclear Bank SA/NV, as the case may be, on or about October 18, 2018, which is the fourth Tokyo business day following the date of this prospectus supplement. This settlement date may affect the trading of the notes.

Joint Book-Running Managers

Prospectus Supplement dated October 12, 2018

TABLE OF CONTENTS

No dealer, salesperson or other person is authorized to give any information or to represent anything not contained in this prospectus supplement, the accompanying prospectus and any related free writing prospectus prepared by us. Neither we nor any of the underwriters take responsibility for or provide assurance as to the reliability of, any other information that others may give you. This prospectus supplement and the accompanying prospectus are an offer to sell only the notes offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. The information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and any related free writing prospectus prepared by us is current only as of their respective dates or the date relating to such information provided in that document. Our business operations, financial condition, results of operations and prospects may have changed since those dates.

MIFID II PRODUCT GOVERNANCE / PROFESSIONAL INVESTORS AND ECPs ONLY TARGET MARKET

Solely for the purposes of each manufacturer’s product approval process, the target market assessment in respect of the notes has led to the conclusion that: (i) the target market for the notes is eligible counterparties and professional clients only, each as defined in Directive 2014/65/EU (as amended, “MiFID II”); and (ii) all channels for distribution of the notes to eligible counterparties and professional clients are appropriate. Any person subsequently offering, selling or recommending the notes (a “distributor”) should take into consideration the manufacturers’ target market assessment; however, a distributor subject to MiFID II is responsible for undertaking its own target market assessment in respect of the notes (by either adopting or refining the manufacturers’ target market assessment) and determining appropriate distribution channels.

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NOTICE TO PROSPECTIVE INVESTORS IN THE EUROPEAN ECONOMIC AREA

None of this prospectus supplement, the accompanying prospectus or any related free writing prospectus is a prospectus for the purposes of the European Union’s Directive 2003/71/EC (as amended or superseded), as implemented in the Member States of the European Economic Area (the “EEA”).

The notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the EEA. For these purposes, a retail investor means a person who is one (or more) of:

Consequently no key information document required by Regulation (EU) No 1286/2014 (as amended, the “PRIIPs Regulation”) for offering or selling the notes or otherwise making them available to retail investors in the EEA has been prepared and therefore offering or selling the notes or otherwise making them available to any retail investor in the EEA may be unlawful under the PRIIPs Regulation.

NOTICE TO PROSPECTIVE INVESTORS IN THE UNITED KINGDOM

The communication of this prospectus supplement, the accompanying prospectus, any related free writing prospectus and any other document or materials relating to the issue of the notes offered hereby is not being made, and such documents and/or materials have not been approved, by an authorized person for the purposes of section 21 of the United Kingdom’s Financial Services and Markets Act 2000, as amended (the “FSMA”). Accordingly, such documents and/or materials are not being distributed to, and must not be passed on to, the general public in the United Kingdom. The communication of such documents and/or materials as a financial promotion is only being made to those persons in the United Kingdom who have professional experience in matters relating to investments and who fall within the definition of investment professionals (as defined in Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the “Financial Promotion Order”)), or who fall within Article 49(2)(a) to (d) of the Financial Promotion Order, or who are any other persons to whom it may otherwise lawfully be made under the Financial Promotion Order (all such persons together being referred to as “relevant persons”). In the United Kingdom, the notes offered hereby are only available to, and any investment or investment activity to which this prospectus supplement, the accompanying prospectus and any related free writing prospectus relates will be engaged in only with, relevant persons. Any person in the United Kingdom that is not a relevant person should not act or rely on this prospectus supplement, the accompanying prospectus or any related free writing prospectus or any of their contents.

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STABILIZATION

IN CONNECTION WITH THIS OFFERING, MIZUHO SECURITIES USA LLC (THE “STABILIZING MANAGER”) (OR ANY PERSON ACTING ON BEHALF OF ANY STABILIZING MANAGER(S)) MAY OVER-ALLOT OR EFFECT TRANSACTIONS WITH A VIEW TO SUPPORTING THE MARKET PRICE OF THE NOTES AT A LEVEL HIGHER THAN THAT WHICH MIGHT OTHERWISE PREVAIL. THIS STABILIZING, IF COMMENCED, MAY BE DISCONTINUED AT ANY TIME. THERE IS NO ASSURANCE THAT THE STABILIZING MANAGER (OR PERSONS ACTING ON BEHALF OF THE STABILIZING MANAGER) WILL UNDERTAKE ANY STABILIZATION ACTION. ANY STABILIZATION ACTION MAY BEGIN ON OR AFTER THE DATE ON WHICH ADEQUATE PUBLIC DISCLOSURE OF THE TERMS OF THE OFFER OF THE NOTES IS MADE AND, IF BEGUN, MAY BE ENDED AT ANY TIME, BUT IT MUST END NO LATER THAN THE EARLIER OF 30 DAYS AFTER THE ISSUE DATE OF THE NOTES AND 60 DAYS AFTER THE DATE OF THE ALLOTMENT OF THE NOTES. ANY STABILIZATION ACTION OR OVER-ALLOTMENT MUST BE CONDUCTED BY THE STABILIZING MANAGER (OR PERSONS ACTING ON BEHALF OF THE STABILIZING MANAGER) IN ACCORDANCE WITH ALL APPLICABLE LAWS AND RULES.

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is this prospectus supplement, which describes the terms of the offering of the notes and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The second part is the accompanying prospectus, which provides more general information. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in the accompanying prospectus or any document incorporated herein and therein by reference, on the other hand, you should rely on the information contained in this prospectus supplement.

References in this prospectus supplement to “$,” “dollars” and “U.S. dollars” are to the currency of the United States of America; references to “¥” and “yen” are to the currency of Japan. As used in this prospectus supplement, unless the context otherwise requires, references to “we,” “us,” “our” or “the Company” refer to the consolidated operations of Aflac Incorporated, and its direct and indirect operating subsidiaries. “Parent Company” refers solely to Aflac Incorporated. “Aflac U.S.” refers solely to our subsidiary, American Family Life Assurance Company of Columbus, an insurance company domiciled in Nebraska. “Aflac Japan” refers solely to our subsidiary, Aflac Life Insurance Japan Ltd., a Japanese stock corporation. “Aflac” refers collectively to Aflac U.S. and Aflac Japan.

The functional currency of Aflac Japan’s insurance operations is the yen. We translate our yen-denominated financial statement accounts into U.S. dollars as follows. Assets and liabilities are translated at end-of-period exchange rates. Realized gains and losses on security transactions are translated at the exchange rate on the trade date of each transaction. Other revenues, expenses and cash flows are translated using average exchange rates for the period. The resulting currency translation adjustments are reported in accumulated other comprehensive income. We include in earnings the realized currency exchange gains and losses resulting from foreign currency transactions.

Aflac Incorporated may, without notice to or consent of the holders of the notes, re-open this offering and issue additional notes having the same ranking, interest rate, maturity date and other terms (except for the issue date, public offering price, and, if applicable, the initial interest payment date) as the notes being offered by this prospectus supplement. The notes and the Senior Debt Indenture (as defined below) under which the notes will be issued do not place any limitation on the amount of unsecured debt that may be incurred by us. Provided that such additional notes are fungible for U.S. federal income tax purposes with any then-existing notes, any additional notes, together with the notes offered by this prospectus supplement, will constitute a single series of debt securities under the Senior Debt Indenture.

You should rely only on the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and any related free writing prospectus. Neither we nor the underwriters have authorized anyone to provide you with additional or different information. Neither we nor the underwriters are making an offer to sell these securities in any jurisdiction where the offer or sale of these securities is not permitted.

The distribution of this prospectus supplement, the accompanying prospectus and any related free writing prospectus and the offer and sale of the notes in certain jurisdictions may be restricted by law. The Company and the underwriters require persons into whose possession this prospectus supplement, the accompanying prospectus and any related free writing prospectus come to inform themselves about and to observe any such restrictions. This prospectus supplement, the accompanying prospectus and any related free writing prospectus do not constitute an offer of, or an invitation to purchase, any of the notes in any jurisdiction in which such offer or invitation would be unlawful.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights information contained elsewhere in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference. This summary sets forth the material terms of this offering, but does not contain all of the information you should consider before investing in our notes. You should read carefully this entire prospectus supplement and the accompanying prospectus, including the documents incorporated by reference herein and therein, before making an investment decision to purchase our notes, especially the risks of investing in our notes discussed under “Risk Factors” contained herein and therein and under “Item 1A. Risk Factors” on page 14 of our Annual Report on Form 10-K for the year ended December 31, 2017, on page 96 of our Quarterly Report on Form 10-Q for the quarter ended June 30, 2018 and on page 90 of our Quarterly Report on Form 10-Q for the quarter ended March 31, 2018 (each of which is incorporated by reference herein) as well as the consolidated financial statements and notes to those consolidated financial statements incorporated by reference herein and therein.

Aflac Incorporated

The Parent Company, Aflac Incorporated, was incorporated in 1973 under the laws of the State of Georgia. The Parent Company is a general business holding company and acts as a management company, overseeing the operations of its subsidiaries by providing management services and making capital available. Its principal business is supplemental health and life insurance, which is marketed and administered through its subsidiaries in the United States and Japan. Most of Aflac’s policies are individually underwritten and marketed through independent agents. Aflac U.S. markets and administers group products through Continental American Insurance Company, branded as Aflac Group Insurance. Our insurance operations in the United States and Japan service the two markets for our insurance business.

We offer voluntary insurance policies in Japan and the United States that provide a layer of financial protection against income and asset loss. We continue to diversify our product offerings in both Japan and the United States. Aflac Japan sells voluntary supplemental insurance products, including cancer plans, general medical indemnity plans, medical/sickness riders, care plans, living benefit life plans, ordinary life insurance plans and annuities. Aflac U.S. sells voluntary supplemental insurance products, including products designed to protect individuals from depletion of assets (accident, cancer, critical illness/care, hospital indemnity, fixed-benefit dental, and vision care plans) and loss-of-income products (life and short-term disability plans).

We are authorized to conduct insurance business in all 50 states, the District of Columbia, several U.S. territories and Japan. Aflac Japan’s revenues, including realized gains and losses on its investment portfolio, accounted for 70% and 69% of our total revenues in the six-month periods ended June 30, 2018 and 2017, respectively. The percentage of our total assets attributable to Aflac Japan was 85% at June 30, 2018, compared with 83% at December 2017.

Our principal executive offices are located at 1932 Wynnton Road, Columbus, Georgia 31999 and our telephone number is (706) 323-3431.

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RISK FACTORS

Investing in our notes involves risk. Please see the risk factors described in “Item 1A. Risk Factors” on page 14 of our Annual Report on Form 10-K for the year ended December 31, 2017, on page 96 of our Quarterly Report on Form 10-Q for the quarter ended June 30, 2018 and on page 90 of our Quarterly Report on Form 10-Q for the quarter ended March 31, 2018, which are incorporated by reference in this prospectus supplement. Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus supplement and the accompanying prospectus. The risks and uncertainties we have described are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business operations. These risks could materially affect our business, results of operations or financial condition and cause the value of our securities to decline. You could lose all or part of your investment.

Risks Relating to Our Senior Debt

Because the notes will be issued by the Parent Company, which is a holding company, the notes will be structurally subordinated to the obligations of our subsidiaries.

The Parent Company is a holding company whose assets primarily consist of the capital stock of its subsidiaries. None of our subsidiaries will guarantee the notes, and our subsidiaries will have no obligation to pay any amounts due on the notes or to provide us with funds to meet our payment obligations on the notes, whether in the form of dividends, distributions, loans or other payments. The holders of the notes will have no direct claim to the assets of our subsidiaries and as a result will have a junior position relative to the claims of creditors of our subsidiaries on their assets and earnings. The supplemental indentures governing the notes will permit our subsidiaries to incur additional indebtedness and will not contain any limitation on the amount of other liabilities that may be incurred by those subsidiaries.

The notes will be our unsecured and unsubordinated obligations and will:

At June 30, 2018, the aggregate amount of our outstanding consolidated indebtedness was $5,315 million, of which none was secured. All unsecured indebtedness of the Parent Company would rank equally in right of payment with the notes. All obligations (including insurance obligations and any preferred stock) of our subsidiaries would be effectively senior to the notes. At June 30, 2018, the consolidated obligations of our subsidiaries reflected on our balance sheet were approximately $112,348 million.

Furthermore, in the event of insolvency, bankruptcy, liquidation, dissolution, receivership, reorganization or similar event involving a subsidiary, the assets of that subsidiary would be used to satisfy claims of policyholders and creditors of the subsidiary rather than the Parent Company’s creditors. As a result of the application of the subsidiary’s assets to satisfy claims of policyholders and creditors, the value of the stock of the subsidiary would be diminished and perhaps rendered worthless. Any such diminution in the value of the

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shares of the Parent Company’s subsidiaries would adversely impact its financial condition and possibly impair its ability to meet its obligations on the debt securities. In addition, any liquidation of the assets of the Parent Company’s subsidiaries to satisfy claims of such subsidiary’s policyholders and creditors might limit or make it impossible for such subsidiary to pay dividends to the Parent Company. Moreover, the dividend capacity of each Aflac U.S. and Aflac Japan is subject to regulatory restrictions, which could further limit or make it impossible for those subsidiaries to pay dividends to the Parent Company. Any such limitation or inability to pay dividends would further impair the Parent Company’s ability to satisfy its obligations under the notes.

The Senior Debt Indenture under which the notes will be issued will contain only limited protection for holders of the notes in the event that the Parent Company is involved in a highly leveraged transaction, reorganization, restructuring, merger or similar transaction in the future.

The Senior Debt Indenture under which the notes will be issued may not sufficiently protect holders of notes in the event the Parent Company is involved in a highly leveraged transaction, reorganization, restructuring, merger or similar transaction. The Senior Debt Indenture will not contain any provisions restricting the Parent Company’s ability to:

Additionally, the Senior Debt Indenture will not require the Parent Company to offer to repurchase or redeem or otherwise modify the terms of any of the notes in connection with a change of control or require that the Parent Company comply with any financial ratios or specified levels of net worth or liquidity. The Parent Company’s ability to recapitalize, incur additional debt and take a number of other actions that are not limited by the terms of the notes could have the effect of diminishing the Parent Company’s ability to make payments on the notes when due.

An active trading market for the notes may not develop.

The notes are new issues of securities with no established trading market, and we do not intend to list the notes on any securities exchange or for quotation in any automated dealer quotation system. We have been informed by the underwriters that they intend to make a market in the notes after the offering is completed. However, the underwriters may cease their market-making at any time. In addition, the liquidity of the trading market in the notes, and the market price quoted for the notes, may be adversely affected by changes in the overall market for fixed income securities and by changes in our financial performance or prospects or in the prospects for companies in our industry generally. In addition, such market-making activity will be subject to limits imposed by the Securities Act of 1933, as amended (the “Securities Act”) and the Securities Exchange Act of 1934, as amended (the “Exchange Act”). As a result, you cannot be sure that an active trading market will develop for the notes. If no active trading market develops, you may not be able to resell your notes at their fair market value or at all.

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Increases in prevailing interest rates could adversely impact the trading price of the notes.

The condition of the financial markets and prevailing interest rates have fluctuated in the past and are likely to fluctuate in the future, and increases in prevailing interest rates could have an adverse effect on the trading price of the notes.

An investment in the notes by a purchaser whose home currency is not yen entails significant risks.

All payments of interest on and the principal of the notes and any redemption price for the notes will be made in yen. An investment in the notes by a purchaser whose home currency is not yen entails significant risks. These risks include the possibility of significant changes in rates of exchange between the holder’s home currency and yen and the possibility of the imposition or subsequent modification of foreign exchange controls.

These risks generally depend on factors over which we have no control, such as economic, financial and political events and the supply of and demand for the relevant currencies. In the past, rates of exchange between yen and certain currencies have been highly volatile, and each holder should be aware that volatility may occur in the future. Fluctuations in any particular exchange rate that have occurred in the past, however, are not necessarily indicative of fluctuations in the rate that may occur during the term of the notes. Depreciation of yen against the holder’s home currency would result in a decrease in the effective yield of the notes below its coupon rate and, in certain circumstances, could result in a loss to a holder.

In a lawsuit for payment on the notes, an investor may bear currency exchange risk.

The Senior Debt Indenture is, and the notes will be, governed by the laws of the State of New York. Under New York law, a New York state court rendering a judgment on the notes would be required to render the judgment in yen. However, the judgment would be converted into U.S. dollars at the exchange rate prevailing on the date of entry of the judgment. Consequently, in a lawsuit for payment on the notes, investors would bear currency exchange risk until a New York state court judgment is entered, which could be for an extended period of time. A federal court sitting in New York with diversity jurisdiction over a dispute arising in connection with the notes would apply the foregoing New York law.

In courts outside of New York, investors may not be able to obtain a judgment in a currency other than U.S. dollars. For example, judgment for money in an action based on the notes in many other U.S. federal or state courts ordinarily would be enforced in the United States only in U.S. dollars. The date used to determine the conversion of yen into U.S. dollars would depend upon various factors, including which court renders the judgment and when the judgment is rendered.

Trading in the clearing systems is subject to minimum denomination requirements.

The terms of the notes provide that notes will be issued with a minimum denomination of ¥100,000,000 and multiples of ¥10,000,000 in excess thereof. It is possible that the clearing systems may process trades which could result in amounts being held in denominations smaller than the minimum denominations. If definitive notes are required to be issued in relation to such notes in accordance with the provisions of the relevant global notes, a holder who does not have the minimum denomination or any integral multiple of ¥10,000,000 in excess thereof in its account with the relevant clearing system at the relevant time may not receive all of its entitlement in the form of definitive notes unless and until such time as its holding satisfies the minimum denomination requirement.

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CURRENCY CONVERSION

As of October 5, 2018, the yen/U.S. $ exchange rate was ¥1.00 = U.S.$0.00881, as announced by the U.S. Federal Reserve Board.

Investors will be subject to foreign exchange risks as to payments of principal and interest that may have important economic and tax consequences to them. See “Risk Factors” in this prospectus supplement.

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USE OF PROCEEDS

We estimate that the net proceeds to us from this offering will be approximately ¥53,071,600,000 after deducting underwriting discounts and estimated offering expenses. We intend to use the net proceeds from this offering for general corporate purposes.

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CAPITALIZATION

The following table sets forth our cash and cash equivalents and our consolidated capitalization as of June 30, 2018 on an actual basis and as adjusted to give effect to the offering of the notes and the planned use of proceeds. See “Use of Proceeds” in this prospectus supplement.

You should read the information in this table together with our consolidated financial statements and the related notes in our Quarterly Report on Form 10-Q for the period ended June 30, 2018, which is incorporated herein by reference.

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RATIO OF EARNINGS TO FIXED CHARGES

The following table sets forth our ratio of earnings to fixed charges for each of the periods indicated. For the purpose of computing the below ratios, earnings consist of income from continuing operations before income taxes excluding interest expense on income tax liabilities, plus fixed charges. Fixed charges consist of interest expense, excluding interest expense on income tax liabilities, interest on investment-type contracts and such portion of rental expense as is estimated to be representative of the interest factors in the leases, all on a pre-tax basis.

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DESCRIPTION OF THE NOTES

Set forth below is a description of the specific terms of the notes. This description supplements, and should be read together with, the description of the general terms and provisions of the securities set forth in the accompanying prospectus under the caption “Description of Debt Securities.” The following description does not purport to be complete and is subject to, and qualified in its entirety by reference to, the indenture dated as of May 21, 2009, as supplemented by a fifteenth supplemental indenture for the 2030 notes, as supplemented by a sixteenth supplemental indenture for the 2033 notes and as supplemented by a seventeenth supplemental indenture for the 2038 notes, which we collectively refer to as the “Senior Debt Indenture,” between Aflac Incorporated, as issuer, and The Bank of New York Mellon Trust Company, N.A., as trustee, which we refer to as the “Trustee,” pursuant to which the notes will be issued. Although for convenience the 2030 notes, the 2033 notes and the 2038 notes are referred to as “notes,” each will be issued as a separate series and will not together have any class voting rights. Accordingly, for purposes of this “Description of Notes,” references to the “notes” shall be deemed to refer to each series of notes separately, and not to the 2030 notes, the 2033 notes and the 2038 notes on any combined basis. All capitalized terms herein that are not defined within this prospectus supplement shall have the same meanings as defined in the Senior Debt Indenture. As used in this “Description of the Notes” section, unless the context otherwise requires, references to “we,” “us,” “our” or “the Company” refer to Aflac Incorporated.

General

The 2030 notes will be issued as a series of senior debt securities under the Senior Debt Indenture and will be limited in aggregate principal amount to ¥29,300,000,000. The 2033 notes will be issued as a series of senior debt securities under the Senior Debt Indenture and will be limited in aggregate principal amount to ¥15,200,000,000. The 2038 notes will be issued as a series of senior debt securities under the Senior Debt Indenture and will be limited in aggregate principal amount to ¥8,900,000,000. The notes will be issued only in denominations of ¥100,000,000 and integral multiples of ¥10,000,000 in excess thereof. Payments of principal of, and interest on, the notes will be made in yen. The provisions of the Senior Debt Indenture pertaining to satisfaction and discharge of the indenture and unclaimed moneys will apply to the notes.

Aflac Incorporated may, without notice to or consent of the holders of the notes, re-open this offering and issue additional notes of a series having the same ranking, interest rate, maturity date and other terms (except for the issue date, public offering price, and, if applicable, the initial interest payment date) as the notes of such series being offered by this prospectus supplement. The notes and the Senior Debt Indenture under which the notes will be issued do not place any limitation on the amount of unsecured debt that may be incurred by us. Provided that such additional notes are fungible for U.S. federal income tax purposes with any then-existing notes, any additional notes of a series, together with the notes of such series offered by this prospectus supplement, will constitute a single series of debt securities under the Senior Debt Indenture.

Except as provided below under “—Tax Redemption,” each series of notes may not be redeemed prior to maturity. Unless previously redeemed or repurchased and canceled, each series of notes will be repayable at par, including Additional Amounts (as defined below), if any, on (i) October 18, 2030 with respect to the 2030 notes, (ii) October 18, 2033 with respect to the 2033 notes and (iii) October 18, 2038 with respect to the 2038 notes, or such earlier date on which the same shall be due and payable in accordance with the terms and conditions of the notes. However, if the maturity date of the notes is not a business day, the notes will be payable on the next succeeding business day and no interest shall accrue for the period from the relevant maturity date to such payment date.

The notes are our unsecured obligations and will rank equally and pari passu with all of our existing and future unsecured senior indebtedness from time to time outstanding.

The notes will not be redeemable prior to maturity, other than as described below in connection with certain events involving United States taxation.

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Issuance in Yen and Payment on the Notes

Initial holders will be required to pay for the notes in yen, and all payments of principal of, the redemption price (if any), and interest and additional amounts (as defined below, if any), on the notes, will be payable in yen.

Investors will be subject to foreign exchange risks as to payments of principal and interest that may have important economic and tax consequences to them. See “Risk Factors” in this prospectus supplement.

Maturity

The entire principal amount of the 2030 notes will mature and become due and payable, together with any accrued and unpaid interest thereon, on October 18, 2030. The entire principal amount of the 2033 notes will mature and become due and payable, together with any accrued and unpaid interest thereon, on October 18, 2033. The entire principal amount of the 2038 notes will mature and become due and payable, together with any accrued and unpaid interest thereon, on October 18, 2038.

Interest

Each 2030 note will bear interest at 1.159% per year, each 2033 note will bear interest at 1.488% per year and each 2038 note will bear interest at 1.750% per year, from the most recent date on which interest has been paid or duly provided for or, if no interest has been paid, from the date of original issuance until such principal amount or overdue installment is paid or made available for payment. We will pay interest semi-annually in arrears on April 18 and October 18 of each year, beginning on April 18, 2019, each of which we refer to as an interest payment date.

Interest payments for the notes shall be computed and paid on the basis of a 360-day year consisting of twelve 30-day months. In the event that any date on which interest is payable on the notes is not a business day, then payment of the interest payable on such date will be made on the next succeeding day that is a business day (and without any interest or other payment in respect of any such delay), except that, if such next succeeding business day is in the next succeeding calendar year, such payment will be made on the immediately preceding business day, in each case with the same force and effect as if such payment was made on the date such payment was originally payable.

The interest payable by us on a note on any interest payment date and on the maturity date, subject to certain exceptions, will be paid to the person in whose name such note is registered at the close of business on or immediately preceding such interest payment date, whether or not a business day. However, interest that we pay on the maturity date or a Redemption Date (as defined below) will be payable to the person to whom the principal will be payable.

Additional Amounts

All payments of principal and interest in respect of the notes will be made free and clear of, and without deduction or withholding for or on account of, any present or future taxes, duties, assessments or other governmental charges of whatsoever nature imposed, levied, collected, withheld or assessed by the United States or any political subdivision or taxing authority of or in the United States (collectively, “Taxes”), unless such withholding or deduction is required by law (see “U.S. Federal Income Tax Considerations” in this prospectus supplement).

In the event such withholding or deduction of Taxes is required by law, subject to the limitations described below, we will pay to the holder or beneficial owner of any note that is a non-U.S. holder (as defined

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under “U.S. Federal Income Tax Considerations for Non-U.S. Holders” in this prospectus supplement) such additional amounts (“Additional Amounts”) as may be necessary in order that every net payment of principal of or interest on the notes (including upon redemption), after deduction or withholding for or on account of such Taxes, will not be less than the amount provided for in such note to be then due and payable before deduction or withholding for or on account of such Taxes.

However, our obligation to pay Additional Amounts shall not apply to:

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For purposes of this section, the acquisition, ownership, enforcement or holding of or the receipt of any payment with respect to a note will not constitute a connection (1) between the holder or beneficial owner and the United States or (2) between a fiduciary, settlor, beneficiary, member or shareholder or other equity owner of, or a person having a power over, such holder or beneficial owner if such holder or beneficial owner is an estate, a trust, a limited liability company, a partnership, a corporation or other entity and the United States.

Any reference in this prospectus supplement and the accompanying prospectus, in the Senior Debt Indenture or in the notes to principal or interest shall be deemed to refer also to Additional Amounts which may be payable under the provisions of this section.

Except as specifically provided in the notes, we will not be required to make any payment with respect to any tax, duty, assessment or other governmental charge imposed by any government or any political subdivision or taxing authority of or in any government or political subdivision.

Tax Redemption

Any series of the notes may be redeemed at our option, in whole but not in part, at a redemption price equal to 100% of the principal amount of the applicable series of notes to be redeemed, together with interest accrued and unpaid on the notes to be redeemed to, but excluding, the date fixed for redemption, at any time, on giving not less than 30 nor more than 60 days’ notice in accordance with “Notices” below if:

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However, no such notice of redemption shall be given earlier than 90 days prior to the earliest date on which we would be, in the case of a redemption for the reasons specified in (a) above, or there would be a substantial likelihood that we would be, in the case of a redemption for the reasons specified in (b) above, obligated to pay such Additional Amounts if a payment in respect of the notes were then due and at the time such notification of redemption is given such circumstance remains in effect.

Prior to the mailing of any notice of redemption pursuant to this section, we will deliver to the Trustee:

Such notice, once delivered by us to the Trustee, will be irrevocable.

Notices

The Trustee will mail notices by first class mail, postage prepaid, to each registered holder’s last known address as it appears in the security register that the Trustee maintains. The Trustee will only mail these notices to the registered holder of the notes, unless we reissue the notes to you or your nominees in fully certificated form.

Prescription

Under New York’s statute of limitations, any legal action to enforce our payment obligations evidenced by the notes or the coupons must be commenced within six years after the payment thereof is due; thereafter our payment obligations will generally become unenforceable.

Further Issues

We may from time to time, without notice to or the consent of the registered holders of the notes, create and issue further notes ranking equally with the notes in all respects. Such further notes may be consolidated and form a single series with the notes and have the same terms as to status, redemption or otherwise as the notes (except for the issue date, public offering price, and, if applicable, the initial interest payment date).

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Book-Entry and Settlement

We have obtained the information in this section concerning Clearstream Banking, S.A., (“Clearstream”) and Euroclear Bank SA/NV (“Euroclear”) and their book-entry systems and procedures from sources that we believe to be reliable. We take no responsibility for an accurate portrayal of this information. In addition, the description of the clearing systems in this section reflects our understanding of the rules and procedures of Clearstream and Euroclear as they are currently in effect. These systems could change their rules and procedures at any time. We have obtained the information in this section concerning Clearstream and Euroclear and their book-entry systems and procedures from sources that we believe to be reliable, but we take no responsibility for the accuracy of this information.

The notes will initially be represented by one or more fully registered global notes. Each such global note will be deposited with, or on behalf of, a common depositary, and registered in the name of the nominee of the common depositary for the accounts of Clearstream and Euroclear. You may hold your interests in the global notes through Clearstream or Euroclear, either as a participant in such systems or indirectly through organizations which are participants in such systems. Clearstream and Euroclear will hold interests in the global notes on behalf of their respective participating organizations or customers through customers’ securities accounts in Clearstream’s or Euroclear’s names on the books of their respective depositaries. Book-entry interests in the notes and all transfers relating to the notes will be reflected in the book-entry records of Clearstream and Euroclear.

The distribution of the notes will be cleared through Clearstream and Euroclear. Any secondary market trading of book-entry interests in the notes will take place through Clearstream and Euroclear participants and will settle in same-day funds. Owners of book-entry interests in the notes will receive payments relating to their notes in yen.

Clearstream and Euroclear have established electronic securities and payment transfer, processing, depositary and custodial links among themselves and others, either directly or through custodians and depositaries. These links allow securities to be issued, held and transferred among the clearing systems without the physical transfer of certificates. Special procedures to facilitate clearance and settlement have been established among these clearing systems to trade securities across borders in the secondary market.

The policies of Clearstream and Euroclear will govern payments, transfers, exchange and other matters relating to the investor’s interest in securities held by them. We have no responsibility for any aspect of the records kept by Clearstream or Euroclear or any of their direct or indirect participants. We also do not supervise these systems in any way.

Clearstream and Euroclear and their participants perform these clearance and settlement functions under agreements they have made with one another or with their customers. You should be aware that they are not obligated to perform or continue to perform these procedures and may modify them or discontinue them at any time.

Except as provided below, owners of beneficial interests in the notes will not be entitled to have the notes registered in their names, will not receive or be entitled to receive physical delivery of the notes in definitive form and will not be considered the owners or holders of the notes under the Senior Debt Indenture, including for purposes of receiving any reports delivered by us or the Trustee pursuant to the Senior Debt Indenture. Accordingly, each person owning a beneficial interest in a note must rely on the procedures of the depositary and, if such person is not a participant, on the procedures of the participant through which such person owns its interest, in order to exercise any rights of a holder of notes.

Clearstream

Clearstream advises that it is incorporated under the laws of Luxembourg as a professional depository. Clearstream holds securities for its customers and facilitates the clearance and settlement of securities

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transactions between its customers through electronic book-entry changes in accounts of its customers, thus eliminating the need for physical movement of certificates. Clearstream provides to its customers, among other things, services for safekeeping, administration, clearance and settlement of internationally traded securities and securities lending and borrowing. Clearstream interfaces with domestic markets in a number of countries.

Clearstream customers are recognized financial institutions around the world, including underwriters, securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations. Indirect access to Clearstream is also available to others, such as banks, brokers, dealers and trust companies that clear through, or maintain a custodial relationship with, a Clearstream customer either directly or indirectly.

The Euroclear System

Euroclear has advised us that the Euroclear System was created in 1968 to hold securities for participants in the Euroclear System and to clear and settle transactions between Euroclear participants through simultaneous electronic book-entry delivery against payment, thus eliminating the need for physical movement of certificates and risk from lack of simultaneous transfers of securities and cash. Transactions may now be settled in many currencies, including U.S. dollars. The Euroclear System provides various other services, including securities lending and borrowing and interfaces with domestic markets in several countries.

The Euroclear System is operated by Euroclear, under contract with Euroclear Clearance System, S.C., a Belgian cooperative corporation. Euroclear conducts all operations, and all Euroclear securities clearance accounts and Euroclear cash accounts are accounts with Euroclear, not the cooperative. The cooperative establishes policy for the Euroclear System on behalf of Euroclear participants. Euroclear participants include banks (including central banks), securities brokers and dealers and other professional financial intermediaries and may include the underwriters. Indirect access to the Euroclear System is also available to other firms that clear through or maintain a custodial relationship with a Euroclear participant, either directly or indirectly.

The Terms and Conditions Governing Use of Euroclear and the related Operating Procedures of the Euroclear System and applicable Belgian law govern securities clearance accounts and cash accounts with Euroclear. Specifically, these terms and conditions govern:

All securities in the Euroclear System are held on a fungible basis without attribution of specific certificates to specific securities clearance accounts. Euroclear acts under the terms and conditions only on behalf of Euroclear participants and has no record of or relationship with persons holding securities through Euroclear participants.

Euroclear further advises that investors that acquire, hold and transfer interests in the notes by book-entry through accounts with Euroclear or any other securities intermediary are subject to the laws and contractual provisions governing their relationship with their intermediary, as well as the laws and contractual provisions governing the relationship between such an intermediary and each other intermediary, if any, standing between themselves and the notes.

Euroclear advises that under Belgian law, investors that are credited with securities on the records of Euroclear have a co-property right in the fungible pool of interests in securities on deposit with Euroclear in an amount equal to the amount of interests in securities credited to their accounts. In the event of the insolvency of Euroclear, Euroclear participants would have a right under Belgian law to the return of the amount and type of interests in securities credited to their accounts with Euroclear. If Euroclear did not have a sufficient amount of

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interests in securities on deposit of a particular type to cover the claims of all Euroclear participants credited with such interests in securities on Euroclear’s records, all Euroclear participants having an amount of interests in securities of such type credited to their accounts with Euroclear would have the right under Belgian law to the return of their pro rata share of the amount of interest in securities actually on deposit.

Under Belgian law, Euroclear is required to pass on the benefits of ownership in any interests in securities on deposit with it, such as dividends, voting rights and other entitlements, to any person credited with such interests in securities on its records.

Clearance and Settlement Procedures

We understand that investors that hold their notes through Clearstream or Euroclear accounts will follow the settlement procedures that are applicable to conventional bonds in registered form. It is intended that notes will be credited to the securities custody accounts of Clearstream and Euroclear holders on the settlement date on a delivery against payment basis. None of the notes may be held through, no trades of the notes will be settled through, and no payments with respect to the notes will be made through, The Depository Trust Company in the United States of America.

We understand that secondary market trading between Clearstream and/or Euroclear participants will occur in the ordinary way following the applicable rules and operating procedures of Clearstream and Euroclear. Secondary market trading will be settled using procedures applicable to conventional bonds in registered form.

You should be aware that investors will only be able to make and receive deliveries, payments and other communications involving the notes through Clearstream and Euroclear on days when those systems are open for business. Those systems may not be open for business on days when banks, brokers and other institutions are open for business in the United States.

In addition, because of time-zone differences, there may be problems with completing transactions involving Clearstream and Euroclear on the same business day as in the United States. U.S. investors who wish to transfer their interests in the notes, or to make or receive a payment or delivery of the notes, on a particular day, may find that the transactions will not be performed until the next business day in Luxembourg or Brussels, depending on whether Clearstream or Euroclear is used.

Clearstream or Euroclear will credit payments to the cash accounts of Clearstream customers or Euroclear participants in accordance with the relevant system’s rules and procedures, to the extent received by its depositary. Clearstream or Euroclear, as the case may be, will take any other action permitted to be taken by a holder under the Senior Debt Indenture on behalf of a Clearstream customer or Euroclear participant only in accordance with its relevant rules and procedures.

Clearstream and Euroclear have agreed to the foregoing procedures in order to facilitate transfers of the notes among participants of Clearstream and Euroclear. However, they are under no obligation to perform or continue to perform those procedures, and they may discontinue those procedures at any time.

Transfer

No service charge will be made for any registration of transfer or exchange of notes, but payment will be required of a sum sufficient to cover any tax or other governmental charge that may be imposed in connection therewith.

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Certain Covenants

The Senior Debt Indenture does not contain any provisions that will restrict the Company from incurring, assuming or becoming liable with respect to any indebtedness or other obligations, whether secured or unsecured, or from paying dividends or making other distributions on its capital stock or purchasing or redeeming its capital stock. The Senior Debt Indenture does not contain any financial ratios or specified levels of net worth or liquidity with which the Company must comply. In addition, the Senior Debt Indenture does not contain any provision that would require that the Company repurchase or redeem or otherwise modify the terms of any of the notes upon a change in control or other events involving the Company which may adversely affect the creditworthiness of the notes.

The Company is not required pursuant to the Senior Debt Indenture to repurchase the notes, in whole or in part, with the proceeds of any sale, transfer or other disposition of any shares of capital stock of any restricted subsidiary (or of any subsidiary having any direct or indirect control of any restricted subsidiary). Further, the Senior Debt Indenture does not provide for any restrictions on the Company’s use of such proceeds.

For a discussion of the covenants contained in the Senior Debt Indenture, including those imposing limitations on liens on restricted subsidiaries and dispositions of stock of restricted subsidiaries, see “Description of Debt Securities—Covenants Applicable to the Debt Securities” in the accompanying prospectus.

About the Trustee

The Bank of New York Mellon Trust Company, N.A. is the Trustee. Subject to the provisions of the Trust Indenture Act of 1939, as amended, the Trustee is under no obligation to exercise any of its powers vested in it by the Senior Debt Indenture at the request of any holder of the notes unless the holder offers the Trustee indemnity or security satisfactory to it against the costs, expenses and liabilities which might result. The Trustee is not required to expend or risk its own funds or otherwise incur personal financial liability in performing its duties if the Trustee reasonably believes that it is not reasonably assured of repayment or adequate indemnity. We have entered, and from time to time may continue to enter, into banking or other relationships with The Bank of New York Mellon Trust Company, N.A. or its affiliates.

The Trustee may resign or be removed with respect to one or more series of debt securities under the Senior Debt Indenture, and a successor trustee may be appointed to act with respect to such series.

Applicable Law

The notes and the Senior Debt Indenture will be governed by and construed in accordance with the laws of the State of New York.

Payment and Paying Agent

We will pay principal of, and any premium, interest and additional amounts on the notes at the office of the paying agent designated by us, except that we may pay interest by check mailed to the registered holder or by wire transfer if the registered holder requests in writing to the Trustee at least 15 days prior to the date for payment.

All moneys we pay to a paying agent of the Trustee for the payment of principal of, or any premium, interest or additional amounts on, a note which remains unclaimed at the end of two years will be repaid to us, and the holder of the note may then look only to us for payment.

The Bank of New York Mellon, London Branch will act as paying agent for the notes.

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U.S. FEDERAL INCOME TAX CONSIDERATIONS

The following is a discussion of U.S. federal income tax considerations generally applicable to the ownership and disposition of the notes by an initial holder of the notes that acquires the notes pursuant to this offering at the public offering price and holds the notes as “capital assets” (generally, property held for investment purposes) for U.S. federal income tax purposes. This discussion is based upon the Internal Revenue Code of 1986, as amended (the “Code”), the Treasury regulations promulgated thereunder (the “Treasury Regulations”), judicial decisions and current administrative rulings and practice, all as in effect and available as of the date hereof and all of which are subject to differing interpretations or change, possibly with retroactive effect. No ruling from the Internal Revenue Service (“IRS”) has been or will be sought on any of the issues discussed herein, and there can be no assurance that the IRS or a court will concur with the conclusions reached below.

This discussion does not address all aspects of U.S. federal income taxation that may be applicable to holders in light of their particular circumstances, or to holders subject to special treatment under U.S. federal income tax law, such as broker-dealers, traders in securities that elect to use a mark-to-market method of accounting for the holders’ securities holdings, banks or other financial institutions, insurance companies, tax-exempt entities (including private foundations) or qualified retirement plans, entities or arrangements that are treated as partnerships for U.S. federal income tax purposes and their partners, dealers in securities or currencies, certain U.S. expatriates, “U.S. holders” (as defined below) whose functional currency is not the U.S. dollar, holders subject to the alternative minimum tax, passive foreign investment companies, persons deemed to sell the notes under the constructive sale provisions of the Code, persons that hold the notes as part of a straddle, hedge, conversion transaction or other integrated transaction for U.S. federal income tax purposes and accrual method taxpayers subject to special tax accounting rules as a result of their use of financial statements under Section 451(b) of the Code . Furthermore, this discussion does not address any other U.S. federal tax consequences (e.g., estate or gift tax or the Medicare tax on net investment income) or any state, local or non-U.S. tax laws. This discussion is not intended to constitute a complete analysis of all tax consequences of the ownership and disposition of the notes. Prospective investors are urged to consult their own tax advisors regarding the U.S. federal, state, local and non-U.S. income and other tax consequences applicable to them in their particular circumstances.

For purposes of this discussion, the term “U.S. holder” means a beneficial owner of a note that, for U.S. federal income tax purposes, is (1) a citizen or individual resident of the United States; (2) a corporation or other entity treated as a corporation for U.S. federal income tax purposes that is created in, or organized under the laws of, the United States, any state thereof, any political subdivision thereof, or the District of Columbia; (3) an estate the income of which is subject to U.S. federal income taxation regardless of its source; or (4) a trust if (a) a court within the United States is able to exercise primary control over its administration and one or more U.S. persons, within the meaning of Section 7701(a)(30) of the Code, have the authority to control all substantial decisions of such trust, or (b) the trust has made an election under the applicable Treasury Regulations to be treated as a U.S. person under the Code. A “non-U.S. holder” is a beneficial owner of a note (other than a partnership or other entity or arrangement treated as a partnership for U.S. federal income tax purposes) that is not a U.S. holder.

If a partnership (including any entity or arrangement treated as a partnership for U.S. federal income tax purposes) beneficially owns the notes, the U.S. federal income tax treatment of a partner in the partnership generally will depend upon the status of the partner and the activities of the partnership. Partners and partnerships are urged to consult their own tax advisors as to the particular U.S. federal income tax consequences applicable to them.

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U.S. Holders

Interest

A U.S. holder that uses the cash method of tax accounting will be required to include in income the U.S. dollar value of the yen-denominated interest payment on a note based on the spot rate of exchange on the date of receipt. No foreign currency exchange gain or loss will be recognized with respect to the receipt of such payment (other than foreign currency exchange gain or loss realized on the disposition of the yen so received, see “—Transactions in Yen,” below).

A U.S. holder that uses the accrual method of tax accounting will accrue interest income on a note in yen and translate the amount accrued into U.S. dollars based on:

A U.S. holder that uses the accrual method of tax accounting will recognize foreign currency exchange gain or loss on the receipt of an interest payment equal to the difference between (i) the value of the yen received as interest, as translated into U.S. dollars using the spot rate of exchange on the date of receipt and (ii) the U.S. dollar amount previously included in income with respect to such payment. Such foreign currency exchange gain or loss will be treated as ordinary income or loss but generally will not be treated as an adjustment to interest income received on the notes.

Disposition of the Notes

Upon the sale, exchange, retirement at maturity, redemption or other taxable disposition of a note (collectively, a “Disposition”), except as noted below with respect to foreign currency exchange gain or loss, a U.S. holder generally will recognize capital gain or loss equal to the difference between the amount realized by such U.S. holder (except to the extent such amount is attributable to accrued but unpaid interest, which will be treated as ordinary interest income if such interest has not been previously included in income) and such U.S. holder’s adjusted tax basis in the note. Subject to the discussion below, the adjusted tax basis of a note to a U.S. holder will generally be the U.S. dollar value of the yen purchase price calculated at the spot rate of exchange on the date of purchase and the amount realized by a U.S. holder upon the Disposition of a note will generally be the U.S. dollar value of the yen received calculated at the spot rate of exchange on the date of Disposition.

If the notes are traded on an established securities market, a U.S. holder that uses the cash method of tax accounting, and if it so elects, a U.S. holder that uses the accrual method of tax accounting, will determine the U.S. dollar values of its adjusted tax basis in the note and the amount realized on the Disposition of a note by translating yen amounts at the spot rate of exchange on the settlement date of the purchase or the Disposition, respectively. The election available to accrual basis U.S. holders discussed above must be applied consistently by the U.S. holder to all debt instruments from year to year and can be changed only with the consent of the IRS.

Except as described below, any gain or loss will be long-term capital gain or loss if the U.S. holder’s holding period for the notes exceeds one year on the date of Disposition. Long-term capital gains recognized by non-corporate U.S. holders are eligible for reduced rates of taxation. The deductibility of capital losses is subject to limitations.

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Gain or loss recognized by a U.S. holder on a Disposition of a note generally will be treated as ordinary income or loss to the extent that the gain or loss is attributable to changes in the yen to U.S. dollar exchange rate during the period in which the U.S. holder held such note. Such foreign currency exchange gain or loss will equal the difference between the U.S. dollar value of the yen purchase price calculated at the spot rate of exchange on the date (1) the note is disposed of (or the spot rate on the settlement date, if applicable) and (2) of purchase (or the spot rate on the settlement date, if applicable). The recognition of such foreign currency exchange gain or loss will be limited to the amount of overall gain or loss realized on the Disposition of a note.

Transactions in Yen

Yen received as interest on, or on a Disposition of, a note will have a tax basis equal to their U.S. dollar value at the time such interest is received or at the time such proceeds from Disposition are received. As discussed above, if the notes are traded on an established securities market, a cash basis U.S. holder (or an electing accrual basis U.S. holder) will determine the U.S. dollar value of the yen by translating the yen received at the spot rate of exchange on the settlement date of the purchase or the Disposition. The amount of gain or loss recognized on a sale or other disposition of such yen will be equal to the difference between (1) the amount of U.S. dollars, or the fair market value in U.S. dollars of the other property received in such sale or other disposition, and (2) the U.S. holder’s adjusted tax basis in such yen. Any such gain or loss generally will be ordinary income or loss and will not be treated as interest income or expense.

A U.S. holder that purchases a note with previously owned yen will generally recognize gain or loss in an amount equal to the difference, if any, between such U.S. holder’s adjusted tax basis in such yen and the U.S. dollar fair market value of such note on the date of purchase. The conversion of U.S. dollars to yen and the immediate use of such yen to purchase a note generally will not result in any exchange gain or loss for a U.S. holder.

Reportable Transaction Reporting

Under applicable Treasury Regulations, a U.S. holder who participates in “reportable transactions”(as defined in the Treasury Regulations) must attach to its U.S. federal income tax return a disclosure statement on IRS Form 8886. The Treasury Regulations could be interpreted to cover transactions generally not regarded as tax shelters, including certain foreign currency transactions. Under the relevant rules, a U.S. holder may be required to treat a foreign currency exchange loss from the notes as a reportable transaction if this loss exceeds the relevant threshold in the Treasury Regulations. U.S. holders are urged to consult their own tax advisors to determine the tax reporting obligations, if any, including any requirement to file IRS Form 8886, with respect to the ownership or disposition of the notes or any related transaction such as the disposition of any yen received in respect of the notes.

Non-U.S. Holders

Interest

Subject to the discussion of the Foreign Account Tax Compliance Act below, a non-U.S. holder will generally not be subject to U.S. federal income or withholding tax on payments of interest on the notes provided that (1) such interest is not effectively connected with the conduct of a trade or business within the United States by the non-U.S. holder (or, if certain tax treaties apply, such interest is not attributable to a permanent establishment or fixed base maintained within the United States by the non-U.S. holder) and (2) the non-U.S. holder (a) does not actually or constructively own 10% or more of the total combined voting power of all classes of our voting stock, (b) is not a controlled foreign corporation related to us directly or constructively through stock ownership (within the meaning of Section 864(d)(4) of the Code), and (c) satisfies certain certification requirements. Such certification requirements will be met if (i) the non-U.S. holder provides its name and

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address, and certifies on an IRS Form W-8BEN or IRS Form W-8BEN-E (or appropriate substitute form), under penalties of perjury, that it is not a U.S. person, or (ii) a securities clearing organization, bank or certain other financial institutions holding the notes on behalf of the non-U.S. holder certifies on IRS Form W-8IMY, under penalties of perjury, that the certification referred to in clause (i) has been received by it and furnishes us or our paying agent with a copy thereof. In addition, we or our paying agent must not have actual knowledge or reason to know that the beneficial owner of the notes is a U.S. person or that any of the information, certifications or statements in the IRS Form W-8BEN or IRS Form W-8BEN-E are incorrect.

If interest on the notes is not effectively connected with the conduct of a trade or business in the United States by a non-U.S. holder but such non-U.S. holder cannot satisfy the other requirements outlined in the preceding paragraph, interest on the notes will generally be subject to U.S. federal withholding tax (currently imposed at a 30% rate), unless the withholding tax rate is reduced or eliminated by an applicable income tax treaty, and such non-U.S. holder is a qualified resident of the treaty country and complies with certain certification requirements.

If interest on the notes is effectively connected with the conduct of a trade or business within the United States by a non-U.S. holder and, if certain tax treaties apply, such interest is attributable to a permanent establishment or fixed base within the United States, then the non-U.S. holder will generally be subject to U.S. federal income tax on the receipt or accrual of such interest on a net income basis in the same manner as if such holder were a U.S. person and, in the case of a non-U.S. holder that is a foreign corporation, may also be subject to an additional branch profits tax (currently imposed at a rate of 30%, or a lower applicable treaty rate) on its effectively connected earnings and profits, subject to adjustments. Any such interest will not also be subject to U.S. federal withholding tax, however, if the non-U.S. holder delivers to us a properly executed IRS Form W-8ECI in order to claim an exemption from U.S. federal withholding tax.

Disposition of the Notes

Except with respect to accrued but unpaid interest, which will generally be exempt from U.S. taxation if a non-U.S. holder meets the requirements as described above under “Interest,” and subject to the discussions of backup withholding and the Foreign Account Tax Compliance Act below, a non-U.S. holder will generally not be subject to U.S. federal income tax (or any withholding thereof) with respect to gain, if any, recognized on the Disposition of the notes unless (1) the gain is effectively connected with the conduct of a trade or business within the United States by the non-U.S. holder and, if certain tax treaties apply, is attributable to a permanent establishment or fixed base of the non-U.S. holder within the United States, or (2) in the case of a non-U.S. holder that is an individual, such holder is present in the United States for 183 or more days in the taxable year in which such Disposition occurs and certain other conditions are satisfied.

Gain that is effectively connected with the conduct of a trade or business in the United States will generally be subject to U.S. federal income tax on a net income basis (but not U.S. withholding tax), in the same manner as if the non-U.S. holder were a U.S. person, and, in the case of a non-U.S. holder that is a foreign corporation, may also be subject to an additional branch profits tax (currently imposed at a rate of 30%, or a lower applicable treaty rate) on its effectively connected earnings and profits, subject to adjustments. An individual non-U.S. holder who is subject to U.S. federal income tax because the non-U.S. holder was present in the United States for 183 days or more during the year of Disposition of the notes will be subject to a flat 30% tax on the gain derived from such Disposition, which may be offset by certain U.S. source capital losses.

Information reporting and backup withholding

A non-U.S. holder will generally be required to comply with certain certification procedures to establish that such holder is not a U.S. person in order to avoid backup withholding with respect to payments of principal and interest on, or the proceeds of a Disposition of, the notes. In addition, we must report annually to the IRS and to each non-U.S. holder the amount of any interest paid to such non-U.S. holder regardless of

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whether any tax was actually withheld. Copies of the information returns reporting such interest payments and the amount withheld may also be made available to the tax authorities in the country in which a non-U.S. holder resides under the provisions of an applicable tax treaty.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules will be allowed as a refund or credit against a non-U.S. holder’s U.S. federal income tax liability, provided the required information is correctly and timely provided to the IRS. The backup withholding rate is currently 24%.

Additional withholding requirements under the Foreign Account Tax Compliance Act

Withholding at a rate of 30% will generally be required in certain circumstances on interest payable on and, after December 31, 2018, gross proceeds from the Disposition of the notes held by or through certain financial institutions (including investment funds), unless such institution (i) enters into, and complies with, an agreement with the IRS to report, on an annual basis, information with respect to interests in, and accounts maintained by, the institution that are owned by certain U.S. persons or by certain non-U.S. entities that are wholly or partially owned by U.S. persons and to withhold on certain payments, or (ii) if required under an intergovernmental agreement between the United States and an applicable foreign country, reports such information to its local tax authority, which will exchange such information with the U.S. authorities. An intergovernmental agreement between the United States and an applicable foreign country, or other guidance, may modify these requirements. Accordingly, the entity through which the notes are held will affect the determination of whether such withholding is required. Similarly, interest payable on and, after December 31, 2018, gross proceeds from the Disposition of the notes held by an investor that is a non-financial non-U.S. entity that does not qualify under certain exemptions generally will be subject to withholding at a rate of 30%, unless such entity either (i) certifies that such entity does not have any “substantial United States owners” or (ii) provides certain information regarding the entity’s “substantial United States owners,” which we will in turn provide to the United States Department of the Treasury. Prospective investors are urged to consult their own tax advisors regarding the possible implications of these rules on an investment in the notes.

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UNDERWRITING

The Parent Company and the underwriters for the offering (the “underwriters”) named below have entered into an underwriting agreement with respect to the notes. Subject to certain conditions, each underwriter has severally agreed to purchase the principal amount of each series of notes indicated in the following table. Mizuho Securities USA LLC, Morgan Stanley & Co. International plc and SMBC Nikko Securities America, Inc. are acting as representatives of the underwriters for the offering.

Pursuant to the underwriting agreement and subject to certain terms and conditions, the underwriters are committed to take and pay for all of the notes being offered, if any are taken.

Notes sold by the underwriters to the public will initially be offered at the initial public offering price set forth on the cover of this prospectus supplement. Any notes sold by the underwriters to securities dealers may be sold at a discount from the initial public offering price of up to 0.30% of the principal amount of the 2030 notes, up to 0.35% of the principal amount of the 2033 notes and up to 0.45% of the principal amount of the 2038 notes. Any such securities dealers may resell any notes purchased from the underwriters to certain other brokers or dealers at a discount from the initial public offering price of up to 0.10% of the principal amount of the 2030 notes, up to 0.15% of the principal amount of the 2033 notes and up to 0.15% of the principal amount of the 2038 notes. If all the notes are not sold at the initial offering price, the underwriters may change the offering price and the other selling terms. The offering of the notes by the underwriters is subject to receipt and acceptance and subject to the underwriters’ right to reject any order in whole or in part.

The notes are new issues of securities with no established trading market, and we do not intend to list the notes on any securities exchange or for quotation in any automated dealer quotations system. We have been advised by the underwriters that the underwriters intend to make a market in the notes but are not obligated to do so and may discontinue market making at any time without notice. No assurance can be given as to the liquidity of the trading market for the notes.

In connection with the offering of the notes, the underwriters may purchase and sell notes in the open market. These transactions may include short sales, stabilizing transactions and purchases to cover positions created by short sales. Short sales involve the sale by the underwriters of a greater principal amount of notes than they are required to purchase in the offering of the notes. Stabilizing transactions consist of certain bids or purchases made for the purpose of preventing or retarding a decline in the market price of the notes while the offering of the notes is in progress.

In connection with this offering, Mizuho Securities USA LLC (the “stabilizing manager”) (or any person acting on behalf of any stabilizing manager(s)) may over-allot or effect transactions with a view to supporting the market price of the notes at a level higher than that which might otherwise prevails. This stabilizing, if commenced, may be discontinued at any time. There is no assurance that the stabilizing manager (or persons acting on behalf of the stabilizing manager) will undertake any stabilization action. Any stabilization action may begin on or after the date on which adequate public disclosure of the terms of the offer of the notes is made and, if begun, may be ended at any time, but it must end no later than the earlier of 30 days after the issue

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date of the notes and 60 days after the date of the allotment of the notes. Any stabilization action or over-allotment must be conducted by the stabilizing manager (or persons acting on behalf of the stabilizing manager) in accordance with all applicable laws and rules.

The underwriters also may impose a penalty bid. This occurs when a particular underwriter repays to the other underwriter a portion of the underwriting discount received by it because the other underwriter has repurchased notes sold by or for the account of such underwriter in stabilizing or short covering transactions.

These activities by the underwriters may stabilize, maintain or otherwise affect the market price of the notes. As a result, the price of the notes may be higher than the price that otherwise might exist in the open market. If these activities are commenced, they may be discontinued by the underwriters at any time. These transactions may be effected in the over-the-counter market or otherwise.

It is expected that delivery of the notes will be made to investors on or about October 18, 2018, which is the fourth Tokyo business day following the date of this prospectus supplement (such settlement being referred to as “T+4”). Under the E.U. Central Securities Depositories Regulation, trades in the secondary market are required to settle in two London business days, unless the parties to any such trade expressly agree otherwise. Also, under Rule 15c6-1 under the Exchange Act, trades in the secondary market are required to settle in two New York business days, unless the parties to any such trade expressly agree otherwise. Accordingly, purchasers who wish to trade notes earlier than the second London business day, or the second New York business day, before October 18, 2018 will be required, by virtue of the fact that the notes initially will settle T+4, to specify an alternative settlement cycle at the time of any such trade to prevent failed settlement, and so should consult their own advisors.

The Parent Company estimates that its share of the total expenses of the offering of the notes, excluding underwriting discounts, will be approximately $250,000.

The Parent Company has agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act.

The underwriters and their respective affiliates are full service financial institutions engaged in various activities, including securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing, market making, brokerage and other financial and non-financial activities and services. Certain of the underwriters and their respective affiliates have, from time to time, performed, and may in the future perform, various financial advisory and investment banking services for the Company and for persons and entities with relationships with the Company, for which they received or will receive customary fees and expenses. An affiliate of Mizuho Securities USA LLC is the administrative agent, and affiliates of a number of other underwriters are lenders, under an unsecured revolving credit facility agreement. In addition, the Company has agreements with affiliates of Mizuho Securities USA LLC and SMBC Nikko Securities America, Inc. to sell the Company’s products at their Japanese bank branches.

In the ordinary course of their various business activities, the underwriters and their respective affiliates, officers, directors and employees may purchase, sell or hold a broad array of investments and actively trade debt and equity securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments for their own account and for the accounts of their customers, and such investment and securities activities may involve or relate to assets, securities and/or instruments of the Company (directly, as collateral securing other obligations or otherwise) and/or persons and entities with relationships with the issuer. If any of the underwriters or their affiliates have a lending relationship with us, certain of those underwriters or their affiliates routinely hedge, and certain other of those underwriters may hedge, their credit exposure to us consistent with their customary risk management policies. Typically, these underwriters and their affiliates would hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities, including potentially the notes offered hereby. Any such credit

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default swaps or short positions could adversely affect future trading prices of the notes offered hereby. The underwriters and their respective affiliates may also make investment recommendations, communicate market color or trading ideas and/or publish or express independent research views in respect of such assets, securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such assets, securities and instruments.

European Economic Area

The notes are not intended to be offered, sold or otherwise made available to any retail investor in the EEA. For the purposes of this provision, the expression “retail investor” means a person who is one (or more) of the following:

United Kingdom

Any invitation or inducement to engage in investment activity (within the meaning of Section 21 of the FSMA) in connection with the issue or sale of the notes may only be communicated or caused to be communicated in circumstances in which Section 21(1) of the FSMA does not apply to the Parent Company.

All applicable provisions of the FSMA must be complied with in respect to anything done by any person in relation to the notes in, from or otherwise involving the United Kingdom.

Hong Kong

The notes may not be offered or sold by means of any document other than (1) in circumstances which do not constitute an offer to the public within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), or (2) to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap.571, Laws of Hong Kong) and any rules made thereunder, or (3) in other circumstances which do not result in the document being a “prospectus” within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), and no advertisement, invitation or document relating to the notes may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the laws of Hong Kong) other than with respect to notes which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap.571, Laws of Hong Kong) and any rules made thereunder.

Japan

The notes have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (Law No. 25 of 1948 of Japan, as amended, the “FIEL”). In respect of the solicitation relating to the notes in Japan, no securities registration statement under Article 4, Paragraph 1 of the FIEL has been filed, since this solicitation constitutes a “solicitation targeting QIIs,” as defined in Article 23-13, Paragraph 1 of the FIEL.

Any investor desiring to acquire the notes must be aware that the notes may not be Transferred (as defined below) to any other person unless such person is a QII.

“QII” means a qualified institutional investor as defined in the Cabinet Ordinance Concerning Definitions under Article 2 of the FIEL (Ordinance No. 14 of 1993 of the Ministry of Finance of Japan, as amended).

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“Transfer” means a sale, exchange, transfer, assignment, pledge, hypothecation, encumbrance or other disposition of all or any portion of notes, either directly or indirectly, to another person. When used as a verb, the terms “Transfer” and “Transferred” shall have correlative meanings.

Singapore

This prospectus supplement has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus supplement and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the notes may not be circulated or distributed, nor may the notes be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (1) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore (the “SFA”), (2) to a relevant person, or any person pursuant to Section 275(1A), and in accordance with the conditions, specified in Section 275 of the SFA or (3) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where the notes are subscribed or purchased under Section 275 of the SFA by a relevant person which is: (a) a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or (b) a trust (where the Trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary of the trust is an individual who is an accredited investor, shares, debentures and units of shares and debentures of that corporation or the beneficiaries’ rights and interest (howsoever described) in that trust shall not be transferred within six months after that corporation or that trust has acquired the notes pursuant to an offer made under Section 275 of the SFA except: (1) to an institutional investor for corporations, under Section 274 of the SFA or to a relevant person defined in Section 275(2) of the SFA, or to any person pursuant to Section 275(1A) or an offer that is made on terms that such shares, debentures and units of shares and debentures of that corporation or such rights and interest in that trust are acquired at a consideration of not less than S$200,000 (or its equivalent in a foreign currency) for each transaction, whether such amount is to be paid for in cash or by exchange of securities or other assets, in accordance with the conditions specified in Section 275 of the SFA; (2) where no consideration is or will be given for the transfer; (3) where the transfer is by operation of law; or (4) pursuant to Section 276(7) of the SFA.

Canada

The notes may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the notes must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts (“NI 33-105”), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

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VALIDITY OF THE NOTES

Certain legal matters as to Georgia law in connection with this offering of notes will be passed upon for us by Audrey Boone Tillman, Esq., Executive Vice President and General Counsel of Aflac Incorporated, and certain legal matters as to New York law in connection with this offering of notes will be passed upon for us by Sidley Austin LLP, New York, New York. The validity of the notes will be passed upon for the underwriters by Sullivan & Cromwell LLP, New York, New York and Sullivan & Cromwell LLP will rely as to all matters of Georgia law upon the opinion of Audrey Boone Tillman, Esq.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC under the Exchange Act. You may read and copy any of this information at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC also maintains an Internet site that contains reports, proxy and information statements and other information about issuers who file electronically with the SEC. The address of that site is http://www.sec.gov. These reports, proxy statements and other information may also be inspected at the offices of the NYSE at 20 Broad Street, New York, New York 10005. General information about us, including our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as any amendments and exhibits to those reports, are available free of charge through our website at www.aflac.com as soon as reasonably practicable after we file them with, or furnish them to, the SEC. Information on our website is not incorporated into this prospectus or our other securities filings and is not a part of these filings. This prospectus supplement relates to a registration statement that we have filed with the SEC relating to the securities to be offered.

This prospectus supplement does not contain all of the information we have included in the registration statement and the accompanying exhibits and schedules in accordance with the rules and regulations of the SEC and we refer you to the omitted information. The statements this prospectus supplement makes pertaining to the content of any contract, agreement or other document that is an exhibit to the registration statement necessarily are summaries of their material provisions and do not describe all exceptions and qualifications contained in those contracts, agreements or documents. You should read those contracts, agreements or documents for information that may be important to you. The registration statement, exhibits and schedules are available at the SEC’s public reference room or through its website.

We “incorporate by reference” into this prospectus supplement information we file with the SEC, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is deemed to be part of this prospectus supplement and later information that we file with the SEC will automatically update and supersede that information. This prospectus supplement incorporates by reference the documents set forth below that we have previously filed with the SEC. These documents contain important information about us and our financial condition.

The following documents listed below, which we have previously filed with the SEC, are incorporated by reference:

All documents filed by us under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act from the date of this prospectus supplement and prior to the termination of the offering of the securities shall also be deemed to be incorporated in this prospectus supplement by reference.

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We will provide a copy of these filings, at no cost, upon your written or oral request to us at the following address or telephone number:

Aflac Incorporated

Office of the Secretary

1932 Wynnton Road

Columbus, Georgia 31999

(706) 323-3431

Exhibits to the filings will not be sent, unless those exhibits have been specifically incorporated by reference in this prospectus supplement.

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PROSPECTUS

Aflac Incorporated

Senior Debt Securities

Subordinated Debt Securities

We may, from time to time, offer to sell senior or subordinated debt securities. This prospectus describes some of the general terms that may apply to these securities.

Specific terms of these securities not provided herein will be provided in one or more supplements to this prospectus. You should read this prospectus and any applicable prospectus supplement carefully before you invest.

You should carefully consider the risks of an investment in these securities. See “Risk Factors” in this prospectus, “Item 1A — Risk Factors” in our most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q, and any other risk factors included in filings we have made with the Securities and Exchange Commission (the “SEC”) that are incorporated herein by reference or set forth in any applicable prospectus supplement that accompanies this prospectus.

Neither the SEC nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus or any prospectus supplement. Any representation to the contrary is a criminal offense.

The date of this prospectus is September 7, 2018.

TABLE OF CONTENTS

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This prospectus relates to a registration statement filed by Aflac Incorporated with the SEC using a “shelf” registration process (the “registration statement”). Under this shelf process as described in the registration statement, we may sell any combination of the securities described in this prospectus in one or more offerings. This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide one or more prospectus supplements that will contain specific information about the terms of that particular offering. Any applicable prospectus supplement may also add, update or change information contained in this prospectus. If there is any inconsistency between the information in this prospectus and any applicable prospectus supplement, you should rely on the information in an applicable prospectus supplement. You should read both this prospectus and any applicable prospectus supplement, together with additional information described under the heading “Where You Can Find More Information.”

The functional currency of Aflac Japan’s (as defined below) insurance operations is the Japanese yen. We translate our yen-denominated financial statement accounts into U.S. dollars as follows. Assets and liabilities are translated at end-of-period exchange rates. Realized gains and losses on security transactions are translated at the exchange rate on the trade date of each transaction. Other revenues, expenses and cash flows are translated using average exchange rates for the period. The resulting currency translation adjustments are reported in accumulated other comprehensive income. We include in earnings the realized currency exchange gains and losses resulting from foreign currency transactions.

The registration statement containing this prospectus, including the exhibits to the registration statement, provides additional information about us and the securities to be offered. The registration statement, including the exhibits, can be read at the SEC website or at the SEC offices mentioned under the heading “Where You Can Find More Information.” General information about us, including our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as any amendments and exhibits to those reports, are available free of charge through our website at www.aflac.com as soon as reasonably practicable after we file them with, or furnish them to, the SEC. Information on our website is not incorporated into this prospectus or our other securities filings and is not a part of these filings.

You should rely only on the information contained in this prospectus and the information to which we have referred you. We have not authorized any other person to provide you with information that is different. This prospectus may only be used where it is legal to sell these securities. The information in this prospectus may only be accurate on the date of this document.

As used in this prospectus, unless the context otherwise requires, references to “we,” “us,” “our” or “the Company” refer to the consolidated operations of Aflac Incorporated and its direct and indirect operating subsidiaries. “Parent Company” refers solely to Aflac Incorporated. “Aflac U.S.” refers solely to our subsidiary, American Family Life Assurance Company of Columbus, an insurance company domiciled in Nebraska. “Aflac Japan” refers solely to our subsidiary, Aflac Life Insurance Japan Ltd., a Japanese stock corporation. “Aflac” refers collectively to Aflac U.S. and Aflac Japan.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

The Private Securities Litigation Reform Act of 1995 provides a “safe harbor” to encourage companies to provide prospective information, so long as those informational statements are identified as forward-looking and are accompanied by meaningful cautionary statements identifying important factors that could cause actual results to differ materially from those included in the forward-looking statements. We desire to take advantage of these provisions. This prospectus or documents filed with the SEC and incorporated by reference herein contain cautionary statements identifying important factors that could cause actual results to differ materially from those projected herein, and in any other statements made by our officials in communications with the financial community and contained in documents filed with the SEC. Forward-looking statements are not based on historical information and relate to future operations, strategies, financial results or other developments. Furthermore, forward-looking information is subject to numerous assumptions, risks and uncertainties. In particular, statements containing words such as “expect,” “anticipate,” “believe,” “goal,” “objective,” “may,” “should,” “estimate,” “intends,” “projects,” “will,” “assumes,” “potential,” “target,” “outlook” or similar words as well as specific projections of future results, generally qualify as forward-looking. We undertake no obligation to update such forward-looking statements.

We caution readers that the following factors, in addition to other factors mentioned from time to time, could cause actual results to differ materially from those contemplated by the forward-looking statements:

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AFLAC INCORPORATED

The Parent Company, Aflac Incorporated, was incorporated in 1973 under the laws of the State of Georgia. The Parent Company is a general business holding company and acts as a management company, overseeing the operations of its subsidiaries by providing management services and making capital available. Its principal business is supplemental health and life insurance, which is marketed and administered through its subsidiaries in the United States and Japan. Most of Aflac’s policies are individually underwritten and marketed through independent agents. Aflac U.S. markets and administers group products through Continental American Insurance Company, branded as Aflac Group Insurance. Our insurance operations in the United States and Japan service the two markets for our insurance business.

We offer voluntary insurance policies in Japan and the United States that provide a layer of financial protection against income and asset loss. We continue to diversify our product offerings in both Japan and the United States. Aflac Japan sells voluntary supplemental insurance products, including cancer plans, general medical indemnity plans, medical/sickness riders, care plans, living benefit life plans, ordinary life insurance plans and annuities. Aflac U.S. sells voluntary supplemental insurance products, including products designed to protect individuals from depletion of assets (accident, cancer, critical illness/care, hospital indemnity, fixed-benefit dental, and vision care plans) and loss-of-income products (life and short-term disability plans).

We are authorized to conduct insurance business in all 50 states, the District of Columbia, several U.S. territories and Japan. Aflac Japan’s revenues, including realized gains and losses on its investment portfolio, accounted for 70% and 69% of our total revenues in the six-month periods ended June 30, 2018 and 2017, respectively. The percentage of our total assets attributable to Aflac Japan was 85% at June 30, 2018, compared with 83% at December 2017.

Our principal executive offices are located at 1932 Wynnton Road, Columbus, Georgia 31999 and our telephone number is (706) 323-3431.

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RISK FACTORS

Investing in our securities involves risk. Please see the risk factors described in “Item 1A — Risk Factors” in our most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q, which are incorporated by reference in this prospectus, as well as any risk factors included in any other filings we have made with the SEC that are incorporated by reference herein or set forth in any applicable prospectus supplement that accompanies this prospectus. Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus. The risks and uncertainties we have described are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business operations, results of operations or financial condition. Additional risk factors may be included in an applicable prospectus supplement relating to a particular series or offering of securities. These risks could materially affect our business operations, results of operations or financial condition and cause the value of our securities to decline. You could lose all or part of your investment.

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USE OF PROCEEDS

Unless otherwise indicated in an applicable prospectus supplement, the net proceeds from the sale of the securities offered by us will be used for general corporate purposes. We may provide additional information on the use of the net proceeds from the sale of the offered securities in an applicable prospectus supplement relating to the offered securities in accordance with SEC rules.

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RATIO OF EARNINGS TO FIXED CHARGES

The following table sets forth our ratio of earnings to fixed charges for each of the periods indicated. For the purpose of computing the below ratios, earnings consist of income from continuing operations before income taxes excluding interest expense on income tax liabilities, plus fixed charges. Fixed charges consist of interest expense, excluding interest expense on income tax liabilities, interest on investment-type contracts and such portion of rental expense as is estimated to be representative of the interest factors in the leases, all on a pre-tax basis.

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DESCRIPTION OF DEBT SECURITIES

Senior Debt Indenture and Subordinated Debt Indenture

We may issue our debt securities, consisting of notes, debentures or other indebtedness, from time to time in one or more series. We will issue any senior debt securities pursuant to the Senior Debt Indenture, dated as of May 21, 2009 between the Parent Company, as issuer, and The Bank of New York Mellon Trust Company, N.A., as trustee (the “Senior Debt Indenture”). We will issue any subordinated debt securities pursuant to the Subordinated Indenture, dated as of September 26, 2012 entered into between the Parent Company, as issuer, and The Bank of New York Mellon Trust Company, N.A., as trustee (the “Subordinated Debt Indenture”). The Senior Debt Indenture and the Subordinated Debt Indenture are incorporated by reference as exhibits to the registration statement of which this prospectus forms a part.

The Senior Debt Indenture and the Subordinated Debt Indenture are substantially similar except that (1) the Subordinated Debt Indenture, unlike the Senior Debt Indenture, provides for debt securities that are specifically made junior in right of payment to other specified indebtedness of the Parent Company and (2) the Senior Debt Indenture, unlike the Subordinated Debt Indenture, restricts the ability of the Parent Company to use the shares of its restricted subsidiaries to secure any indebtedness, unless an equal and ratable security interest in these subsidiary shares is granted to the holders of the senior debt securities. Neither the Senior Debt Indenture nor the Subordinated Debt Indenture limits the aggregate principal amount of indebtedness that we may issue from time to time.

The following description provides a general summary of the material terms and conditions of the Senior Debt Indenture, the Subordinated Debt Indenture and the debt securities to be issued pursuant to these indentures.

The following discussion is only a summary. The indentures may contain language that expands upon or limits the statements made in this prospectus. Accordingly, we strongly encourage you to refer to the indentures, as well as any applicable prospectus supplements for any debt securities offered, for a complete understanding of the terms and conditions applicable to the indentures and the debt securities.

Senior and Subordinated Debt Securities

The debt securities will be our unsecured senior or subordinated obligations. The term “senior” is generally used to describe debt obligations that entitle the holders to receive payment of principal and interest upon the happening of certain events prior to the holders of “subordinated” debt. Events that can trigger the right of holders of senior indebtedness to receive payment of principal and interest prior to payments to the holders of subordinated indebtedness include insolvency, bankruptcy, liquidation, dissolution, receivership, reorganization or an event of default under the Senior Debt Indenture.

We may issue the senior debt securities, pursuant to the Senior Debt Indenture, in one or more series. All series of senior debt securities issued under the Senior Debt Indenture will be equal in ranking. The senior debt securities also will rank equally with all our other unsecured indebtedness, other than unsecured indebtedness expressly designated by the holders thereof to be subordinate to our senior debt securities.

The senior indebtedness issued pursuant to the Senior Debt Indenture will rank junior and be subordinate to any indebtedness of our subsidiaries. In the event of an insolvency, bankruptcy, liquidation, dissolution, receivership, reorganization or similar event involving a subsidiary, the assets of that subsidiary would be used to satisfy claims of policyholders and creditors of the subsidiary rather than our creditors. As a result of the application of the subsidiary’s assets to satisfy claims of policyholders and creditors, the value of the stock of the subsidiary would be diminished and perhaps rendered worthless. Any such diminution in the value of the shares of our subsidiaries would adversely impact our financial condition and possibly impair our ability to meet our obligations on the debt securities. In addition, any liquidation of the assets of the Parent Company’s subsidiaries

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to satisfy claims of the subsidiary’s policyholders and creditors might limit or make it impossible for such subsidiary to pay dividends to us. Any such limitation or inability to pay dividends to the Parent Company would further impair the ability of the Parent Company to satisfy its obligations under the debt securities.

The debt securities issued under the Subordinated Debt Indenture will be subordinate in right of payment in respect of principal, any premium and interest owing under the subordinated debt securities to all the senior indebtedness of the Parent Company in the manner described below under the caption “Subordination Under the Subordinated Debt Indenture.”

Prospectus Supplements

We will provide one or more prospectus supplements to accompany this prospectus for each series of debt securities we offer. In an applicable prospectus supplement, we will describe the following terms and conditions of the series of debt securities that we are offering, to the extent applicable:

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Holders of the debt securities may present their securities for exchange and may present registered debt securities for transfer in the manner described in an applicable prospectus supplement. Except as limited by the applicable indenture, we will provide these services without charge, other than any tax or other governmental charge payable in connection with the exchange or transfer.

Debt securities may bear interest at a fixed rate or a floating rate as specified in an applicable prospectus supplement. In addition, if specified in an applicable prospectus supplement, we may sell debt securities bearing no interest or interest at a rate that at the time of issuance is below the prevailing market rate, or at a discount below their stated principal amount. We will describe in an applicable prospectus supplement the special United States federal income tax considerations applicable to these discounted debt securities.

We may issue debt securities with the principal amount payable on any principal payment date, or the amount of interest payable on any interest payment date, to be determined by referring to one or more currency exchange rates, commodity prices, equity indices or other factors. Holders of such debt securities may receive a principal amount on any principal payment date, or interest payments on any interest payment date, that are greater or less than the amount of principal or interest otherwise payable on such dates, depending upon the value on such dates of applicable currency, commodity, equity index or other factors. An applicable prospectus supplement will contain information as to how we will determine the amount of principal or interest payable on any date, as well as the currencies, commodities, equity indices or other factors to which the amount payable on that date relates and certain additional tax considerations.

Global Debt Securities

We may issue registered debt securities in global form. This means that one “global” debt security would be issued to represent one or more registered debt securities. The denomination of the global debt security would equal the aggregate principal amount of all registered debt securities represented by that global debt security.

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We will deposit any registered debt securities issued in global form with a depositary, or with a nominee of the depositary, that we will name in an applicable prospectus supplement. Any person holding an interest in the global debt security through the depositary will be considered the “beneficial” owner of that interest. A “beneficial” owner of a security is able to enjoy rights associated with ownership of the security, even though the beneficial owner is not recognized as the legal owner of the security. The interest of the beneficial owner in the security is considered the “beneficial interest.” We will register the debt securities in the name of the depositary or the nominee of the depositary, as appropriate.

The depositary or its nominee may only transfer a global debt security in its entirety and only in the following circumstances:

These restrictions on transfer would not apply to a global debt security after the depositary or its nominee, as applicable, exchanged the global debt security for registered debt securities issued in definitive form.

We will describe the specific terms of the depositary arrangement with respect to any series of debt securities represented by a registered global security in an applicable prospectus supplement. We anticipate that the following provisions will apply to all depositary arrangements for debt securities represented by a registered global security.

Ownership of beneficial interests in a registered global security will be limited to (1) participants that have accounts with the depositary for the registered global security and (2) persons that may hold interests through those participants. Upon the issuance of a registered global security, the depositary will credit each participant’s account on the depositary’s book-entry registration and transfer system with the principal amount of debt securities represented by the registered global security beneficially owned by that participant. Initially, the dealers, underwriters or agents participating in the distribution of the debt securities will designate the accounts that the depositary should credit.

Ownership of beneficial interests in the registered global security will be shown on, and the transfer of ownership interests will be effected only through, records maintained by the depositary for the registered global security, with respect to interests of participants, and on the records of participants, with respect to interests of persons holding through participants. The laws of some states may require that purchasers of securities regulated by the laws of those states take physical delivery of the securities in definitive form. Those laws may impair the ability to own, transfer or pledge beneficial interests in registered global securities.

As long as the depositary for a registered global security, or its nominee, is the registered owner of the registered global security, that depositary or its nominee will be considered the sole owner or holder of the debt securities represented by the registered global security for all purposes under the applicable indenture. Owners of beneficial interests in a registered global security generally will not:

Accordingly, each person owning a beneficial interest in a registered global security must rely on the procedures of the depositary for the registered global security and, if that person owns through a participant, on the procedures of the participant through which that person owns its interest, to exercise any rights of a holder under the applicable indenture.

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We understand that under existing industry practices, if we request any action of holders of debt securities or if an owner of a beneficial interest in a registered global security desires to give or take any action that a holder of debt securities is entitled to give or take under the applicable indenture, the depositary for the registered global security would authorize the participants holding the relevant beneficial interests to give or take the action, and the participants would authorize beneficial owners owning through the participants to give or take the action or would otherwise act upon the instructions of beneficial owners owning through them.

We will make payments of principal, any premium and any interest on a registered global security to the depositary or its nominee. None of the Parent Company, the indenture trustee or any other agent of the Parent Company or of the indenture trustee will have any responsibility or liability for any aspect of the records relating to, or payments made on account of, beneficial ownership interests in the registered global security or for maintaining, supervising or reviewing any records relating to the beneficial ownership interests.

We expect that the depositary for any registered global security, upon receipt of any payment of principal, premium or interest in respect of the registered global security, will immediately credit participants’ accounts with payments in amounts proportionate to their respective beneficial interests in the registered global security as shown on the records of the depositary.

We also expect that standing customer instructions and customary practices will govern payments by participants to owners of beneficial interests in the registered global security owned through the participants.

We will issue our debt securities in definitive form in exchange for a registered global security, if the depositary for such registered global security is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency registered under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and if a successor depositary registered as a clearing agency under the Exchange Act is not appointed within 90 days. In addition, we may at any time and in our sole discretion determine not to have any of the debt securities of a series represented by a registered global security and, in such event, will issue debt securities of the series in definitive registered form in exchange for the registered global security.

We will register any debt securities issued in definitive form in exchange for a registered global security in such name or names as the depositary shall instruct the indenture trustee. We expect that the depositary will base these instructions upon directions received by the depositary from participants with beneficial interests in the registered global security.

We also may issue bearer debt securities of a series in global form. We will deposit these global bearer securities with a common depositary or with a nominee for the depositary identified in an applicable prospectus supplement. We will describe the specific terms and procedures of the depositary arrangement for the bearer debt securities in an applicable prospectus supplement. We also will describe in an applicable prospectus supplement any specific procedures for the issuance of debt securities in definitive form in exchange for a bearer global security.

Covenants Applicable to the Debt Securities

Limitations on Liens. Under the Senior Debt Indenture, so long as any debt securities are outstanding, neither we nor any of our restricted subsidiaries may use any voting stock of a restricted subsidiary as security for any of our debt or other obligations unless any debt securities issued under the Senior Debt Indenture are secured to the same extent as and for so long as that debt or other obligation is so secured. This restriction does not apply to liens existing at the time a corporation becomes our restricted subsidiary or any renewal or extension of any such existing lien and does not apply to shares of subsidiaries that are not “restricted subsidiaries.”

To qualify as our “subsidiary,” as defined in the Senior Debt Indenture, we must control, either directly or indirectly, more than 50% of the outstanding shares of voting stock of the corporation. The Senior Debt Indenture

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defines voting stock as any class or classes of stock having general voting power under ordinary circumstances to elect a majority of the board of directors of the corporation in question, except that stock that carries only the right to vote conditionally on the happening of an event is not considered voting stock.

As defined in the Senior Debt Indenture, our “restricted subsidiaries” include (1) Aflac U.S., so long as it remains our subsidiary; (2) any other present or future subsidiary of the Parent Company, the consolidated total assets of which constitute at least 20% of our total consolidated assets (which, as of the date of this prospectus, includes Aflac Japan); and (3) any successor to any such subsidiary.

Consolidation, Merger and Sale of Assets. Both the Senior Debt Indenture and Subordinated Debt Indenture provide that we will not consolidate with or merge into any other person or convey, transfer or lease our assets substantially as an entirety to any person, and no person may consolidate with or merge into us, unless:

This covenant would not apply to the direct or indirect conveyance, transfer or lease of all or any portion of the stock, assets or liabilities of any of our wholly owned subsidiaries to us or to our other wholly owned subsidiaries.

The limitations on the transactions described above do not apply to a recapitalization, change of control, or highly leveraged transaction unless the transaction involves a consolidation or merger into a third party, or a sale, other than for cash to a third party of all or substantially all of our assets, or a purchase by us of all or substantially all of the assets of a third party. In addition, the indentures do not include any provisions that would increase interest, provide an option to dispose of securities at a fixed price, or otherwise protect debt security holders in the event of any recapitalization, change of control, or highly leveraged transaction.

Limitations on Dispositions of Stock of Restricted Subsidiaries. Both the Senior Debt Indenture and Subordinated Debt Indenture provide that, except in a transaction otherwise governed by such indenture, neither we nor any of our restricted subsidiaries may issue, sell, assign, transfer or otherwise dispose of any of the voting stock of a restricted subsidiary so long as any of the debt securities remain outstanding. However, exceptions to this restriction include situations where:

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The indentures do not restrict the transfer of assets from a restricted subsidiary to any other person, including us or another of our subsidiaries.

Events of Default

Unless we provide other or substitute events of default in an applicable prospectus supplement, the following events will constitute an event of default under both the Senior Debt Indenture and the Subordinated Debt Indenture:

If an event of default with respect to any debt securities of any series outstanding under either of the indentures shall occur and be continuing, the trustee under such indenture or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series may declare, by notice as provided in the applicable indenture, the principal amount (or such lesser amount as may be provided for in the debt securities of that series) of all the debt securities of that series outstanding to be due and payable immediately; provided that, in the case of an event of default involving certain events of bankruptcy, insolvency or reorganization, acceleration is automatic; and, provided further, that after such acceleration, but before a judgment or decree based on acceleration, the holders of a majority in aggregate principal amount of the outstanding debt securities of that series may, under certain circumstances, rescind and annul such acceleration if all events of default, other than the nonpayment of accelerated principal, have been cured or waived. Upon the acceleration of the maturity of original issue discount securities, an amount less than the principal amount thereof will become due and payable. Reference is made to an applicable prospectus supplement relating to any original issue discount securities for the particular provisions relating to acceleration of maturity thereof.

Both the Senior Debt Indenture and Subordinated Debt Indenture entitle the trustee to obtain assurances of indemnity or security reasonably satisfactory to it by the debt security holders for any actions taken by the trustee at the request of the security holders. The right of the indenture trustee to obtain assurances of indemnity or security is subject to the indenture trustee carrying out its duties with a level of care or standard of care that is

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generally acceptable and reasonable under the circumstances. An indemnity or indemnification is an undertaking by one party to reimburse another upon the occurrence of an anticipated loss.

Subject to the right of the indenture trustee to indemnification as described above and except as otherwise described in the indentures, the indentures provide that the holders of a majority of the aggregate principal amount of the affected outstanding debt securities of each series, treated as one class, may direct the time, method and place of any proceeding to exercise any right or power conferred in the indentures or for any remedy available to the trustee.

The Senior Debt Indenture and Subordinated Debt Indenture provide that no holders of debt securities may institute any action against us, except for actions for payment of overdue principal, any premium or interest, unless:

Under both the Senior Debt Indenture and Subordinated Debt Indenture, we will file annually with the trustee a certificate either stating that no default exists or specifying any default that does exist.

Discharge, Defeasance and Covenant Defeasance

If indicated in an applicable prospectus supplement, we may discharge or defease our obligations under either the Senior Debt Indenture or the Subordinated Debt Indenture as set forth below.

We may discharge certain obligations to holders of any series of debt securities issued under either the Senior Debt Indenture or the Subordinated Debt Indenture which have not already been delivered to the trustee for cancellation and which have either become due and payable or are by their terms due and payable within one year (or scheduled for redemption within one year) by irrevocably depositing with the trustee cash or, in the case of debt securities payable only in U.S. dollars, U.S. government obligations (as defined in either indenture), as trust funds in an amount certified to be sufficient to pay when due, whether at maturity, upon redemption or otherwise, the principal of (and premium, if any) and interest on such debt securities.

If indicated in an applicable prospectus supplement, we may elect either (i) to defease and be discharged from any and all obligations with respect to the debt securities of or within any series (except as otherwise provided in the relevant indenture) (“defeasance”) or (ii) to be released from our obligations with respect to certain covenants applicable to the debt securities of or within any series (“covenant defeasance”), upon the deposit with the relevant trustee, in trust for such purpose, of money and/or government obligations which, through the payment of principal and interest in accordance with their terms, will provide money in an amount sufficient, without reinvestment, to pay the principal of (and premium, if any) or interest on such debt securities to maturity or redemption, as the case may be, and any mandatory sinking fund or analogous payments thereon. As a condition to defeasance or covenant defeasance, we must deliver to the trustee an opinion of counsel to the effect that the holders of such debt securities will not recognize income, gain or loss for federal income tax purposes as a result of such defeasance or covenant defeasance and will be subject to federal income tax on the same amounts and in the same manner and at the same times as would have been the case if such defeasance or covenant defeasance had not occurred. Such opinion of counsel, in the case of defeasance under clause (i) above, must refer to and be based upon a ruling of the Internal Revenue Service or a change in applicable federal income tax law occurring

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after the date of the relevant indenture. In addition, in the case of either defeasance or covenant defeasance, we shall have delivered to the trustee (i) an officers’ certificate to the effect that the relevant debt securities exchange(s) have informed us that neither such debt securities nor any other debt securities of the same series, if then listed on any securities exchange, will be delisted as a result of such deposit, and (ii) an officers’ certificate and an opinion of counsel, each stating that all conditions precedent with respect to such defeasance or covenant defeasance have been complied with.

We may exercise our defeasance option with respect to such debt securities notwithstanding our prior exercise of our covenant defeasance option.

If we exercise our discharge or defeasance option, payment of the affected debt securities may not be accelerated because of an event of default. If we exercise our covenant defeasance option, payment of the affected debt securities may not be accelerated by reason of a default or an event of default with respect to the covenants that have been defeased. If, however, acceleration of the indebtedness under the debt securities occurs by reason of another event of default, the value of the money and government obligations in the defeasance trust on the date of acceleration could be less than the principal and interest then due on the affected securities because the required defeasance deposit is based upon scheduled cash flow rather than market value, which will vary depending upon interest rates and other factors.

Modification of the Indentures

Both the Senior Debt Indenture and Subordinated Debt Indenture provide that we and the trustee may enter into supplemental indentures without the consent of the holders of debt securities to:

The Senior Debt Indenture and Subordinated Debt Indenture also permit us and the trustee, with the consent of the holders of at least a majority in aggregate principal amount of outstanding affected debt securities of all series issued under the relevant indenture, voting as one class, to change, in any manner, the relevant indenture and the rights of the holders of debt securities issued under that indenture. However, the consent of each holder of an affected debt security is required for changes that:

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The Subordinated Debt Indenture may not be amended to alter the subordination of any outstanding subordinated debt securities without the consent of each holder of then outstanding senior indebtedness that would be adversely affected by the amendment.

Subordination Under the Subordinated Debt Indenture

The Subordinated Debt Indenture provides that payment of the principal, any premium and interest on debt securities issued under the Subordinated Debt Indenture will be subordinate and junior in right of payment, to the extent and in the manner set forth in that indenture, to all our senior indebtedness. The Subordinated Debt Indenture defines senior indebtedness as the principal, any premium and interest on all our indebtedness, whether incurred prior to or after the date of the indenture, which is:

Senior indebtedness also includes all deferrals, renewals, extensions and refundings of, and amendments, modifications and supplements to the indebtedness listed above.

Senior indebtedness does not include:

The Subordinated Debt Indenture does not limit the amount of senior indebtedness that we can incur.

The holders of all senior indebtedness will be entitled to receive payment of the full amount due on that indebtedness before the holders of any subordinated debt securities or coupons relating to those subordinated debt securities receive any payment on account of such subordinated debt securities or coupons, in the event:

We may not make any payment of the principal or interest on the subordinated debt securities or coupons during a continued default in payment of any senior indebtedness or if any event of default exists under the terms of any senior indebtedness.

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Governing Law

The Senior Debt Indenture and the Subordinated Debt Indenture are governed by, and construed in accordance with, the laws of the State of New York, except to the extent that the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”), is applicable, in which case the Trust Indenture Act will govern.

The Indenture Trustees

The Bank of New York Mellon Trust Company, N.A. is trustee under each of the Senior Debt Indenture and the Subordinated Debt Indenture.

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REGISTRATION, TRANSFER AND PAYMENT OF CERTIFICATED SECURITIES

If we ever issue securities in certificated form, those securities may be presented for registration, transfer and payment at the office of the registrar or at the office of any transfer agent we designate and maintain. The registrar or transfer agent will make the registration or transfer only if it is satisfied with the documents of title and identity of the person making the request. There will not be a service charge for any exchange or registration of transfer of the securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in connection with the exchange. At any time we may change transfer agents or approve a change in the location through which any transfer agent acts. We also may designate additional transfer agents for any securities at any time.

We will not be required to issue, exchange or register the transfer of any security to be redeemed for a period of 15 days before the selection of the securities to be redeemed. In addition, we will not be required to exchange or register the transfer of any security that was selected, called or is being called for redemption, except the unredeemed portion of any security being redeemed in part.

We will pay principal, any premium, interest and any amounts payable on any certificated securities at the offices of the paying agents we may designate from time to time. Generally, we will pay interest on a security on any interest payment date to the person in whose name the security is registered at the close of business on the regular record date for that payment.

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PLAN OF DISTRIBUTION

We may sell the securities covered by this prospectus in any of three ways (or in any combination) from time to time:

In addition, we may enter into derivative or other hedging transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If any applicable prospectus supplement so indicates, in connection with such a derivative or other hedging transaction, the third parties may, pursuant to this prospectus and any applicable prospectus supplement, sell securities covered by this prospectus and any applicable prospectus supplement. If so, the third party may use securities borrowed from others to settle such sales and may use securities received from us to close out any related short positions. We may also loan or pledge securities covered by this prospectus and any applicable prospectus supplement to third parties, who may sell the loaned securities or, in an event of default in the case of a pledge, sell the pledged securities pursuant to this prospectus and any applicable prospectus supplement.

Any applicable prospectus supplement will set forth the terms of the offering of the securities covered by this prospectus, including:

Unless an applicable prospectus supplement states otherwise, all amounts payable in respect of the securities, including the purchase price, will be payable in U.S. dollars. Any public offering price or purchase price and any discounts, commissions, concessions or other items constituting compensation allowed or reallowed or paid to underwriters, dealers or agents may be changed from time to time.

Underwriters or the third parties described above may offer and sell the offered securities from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price, at market prices or prices related thereto or at varying prices determined at the time of sale. If underwriters are used in the sale of any securities, the securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions described above. The securities may be either offered to the public through underwriting syndicates represented by managing underwriters, or directly by underwriters. Generally, the underwriters’ obligations to purchase the securities will be subject to certain conditions precedent. The underwriters will be obligated to purchase all of the securities if they purchase any of the securities.

We may sell the securities through agents from time to time. If required by applicable law, any applicable prospectus supplement will name any agent involved in the offer or sale of the securities and any commissions we pay to them. Generally, unless otherwise indicated in any applicable prospectus supplement, any agent will be acting on a best efforts basis for the period of its appointment.

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We may authorize underwriters, dealers or agents to solicit offers by certain purchasers to purchase the securities from us at the public offering price set forth in any applicable prospectus supplement or other prices pursuant to delayed delivery or other contracts providing for payment and delivery on a specified date in the future. Any delayed delivery contracts will be subject only to those conditions set forth in any applicable prospectus supplement, and any applicable prospectus supplement will set forth any commissions we pay for solicitation of these delayed delivery contracts.

Each underwriter, dealer and agent participating in the distribution of any offered securities that are issuable in bearer form will agree that it will not offer, sell, resell or deliver, directly or indirectly, offered securities in bearer form in the United States or to U.S. persons except as otherwise permitted by Treasury Regulations Section 1.163-5(c)(2)(i)(D).

Offered securities may also be offered and sold, if so indicated in any applicable prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more remarketing firms, acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreements, if any, with us and its compensation will be described in any applicable prospectus supplement.

Agents, underwriters and other third parties described above may be entitled under relevant underwriting or other agreements to indemnification by us against certain civil liabilities under the Securities Act of 1933, as amended (the “Securities Act”) or to contribution with respect to payments which the agents, underwriters or other third parties may be required to make in respect thereof. Agents, underwriters and such other third parties may be customers of, engage in transactions with, or perform services for us in the ordinary course of business.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC under the Exchange Act. You may read and copy any of this information at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC also maintains an Internet site that contains reports, proxy and information statements and other information about issuers who file electronically with the SEC. The address of that site is http://www.sec.gov. These reports, proxy statements and other information may also be inspected at the offices of the NYSE at 20 Broad Street, New York, New York 10005. General information about us, including our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as any amendments and exhibits to those reports, are available free of charge through our website at www.aflac.com as soon as reasonably practicable after we file them with, or furnish them to, the SEC. Information on our website is not incorporated into this prospectus or our other securities filings and is not a part of these filings.

This prospectus relates to a registration statement that we have filed with the SEC relating to the securities to be offered. This prospectus does not contain all of the information we have included in the registration statement and the accompanying exhibits and schedules in accordance with the rules and regulations of the SEC and we refer you to the omitted information. The statements this prospectus makes pertaining to the content of any contract, agreement or other document that is an exhibit to the registration statement necessarily are summaries of their material provisions and do not describe all exceptions and qualifications contained in those contracts, agreements or documents. You should read those contracts, agreements or documents for information that may be important to you. The registration statement, exhibits and schedules are available at the SEC’s public reference room or through its website.

We “incorporate by reference” into this prospectus information we file with the SEC, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is deemed to be part of this prospectus and later information that we file with the SEC will automatically update and supersede that information. This prospectus incorporates by reference the documents set forth below that we have previously filed with the SEC. These documents contain important information about us and our financial condition.

The following documents listed below, which we have previously filed with the SEC, are incorporated by reference:

All documents filed by us under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act from the date of this prospectus and prior to the termination of the offering of the securities shall also be deemed to be incorporated in this prospectus by reference.

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We will provide a copy of these filings, at no cost, upon your written or oral request to us at the following address or telephone number:

Aflac Incorporated

Office of the Secretary

1932 Wynnton Road

Columbus, Georgia 31999

(706) 323-3431

Exhibits to the filings will not be sent, unless those exhibits have been specifically incorporated by reference in this prospectus.

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LEGAL MATTERS

Unless otherwise indicated in an applicable prospectus supplement, certain legal matters as to Georgia law in connection with the offering of the debt securities will be passed upon for us by Audrey Boone Tillman, Esq., Executive Vice President and General Counsel of Aflac Incorporated and certain legal matters as to New York law in connection with the offering of the debt securities will be passed upon for us by Sidley Austin LLP, New York, New York. Additional legal matters may be passed on for us, or any underwriters, dealers or agents, by counsel which we will name in an applicable prospectus supplement.

EXPERTS

The consolidated financial statements and schedules of Aflac Incorporated and subsidiaries as of December 31, 2017 and 2016, and for each of the years in the three-year period ended December 31, 2017, and management’s assessment of the effectiveness of internal control over financial reporting as of December 31, 2017 have been incorporated by reference herein in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

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