Use these links to rapidly review the document
Prospectus TABLE OF CONTENTS
ABOUT THIS PROSPECTUS
INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Table of Contents

Filed pursuant to Rule 497
Registration No. 333-174716

PROSPECTUS SUPPLEMENT
(To prospectus dated October 28, 2011)

14,280,000 Shares

Common Stock

---

                We are offering for sale 14,280,000 shares of our common stock.

                Ares Capital Corporation is a specialty finance company that is a closed-end, non-diversified management investment company incorporated in Maryland. We have elected to be regulated as a business development company under the Investment Company Act of 1940 and the rules and regulations promulgated thereunder. Our investment objective is to generate both current income and capital appreciation through debt and equity investments. We invest primarily in first and second lien senior loans and mezzanine debt, which in some cases includes an equity component. To a lesser extent, we also make equity investments.

                We are externally managed by Ares Capital Management LLC, a wholly owned subsidiary of Ares Management LLC, a global alternative asset manager and a Securities and Exchange Commission ("SEC") registered investment adviser with approximately $46 billion of total committed capital under management as of December 31, 2011. Ares Operations LLC, a wholly owned subsidiary of Ares Management LLC, provides the administrative services necessary for us to operate.

                Our common stock is traded on The NASDAQ Global Select Market under the symbol "ARCC." On January 19, 2012, the last reported sales price of our common stock on The NASDAQ Global Select Market was $16.09 per share. The net asset value per share of our common stock at September 30, 2011 (the last date prior to the date of this prospectus supplement on which we determined net asset value) was $15.13.

                Investing in our common stock involves risks that are described in the "Risk Factors" section beginning on page 27 of the accompanying prospectus, including the risk of leverage.

                This prospectus supplement and the accompanying prospectus concisely provide important information about us that you should know before investing in our common stock. Please read this prospectus supplement and the accompanying prospectus before you invest and keep it for future reference. We file annual, quarterly and current reports, proxy statements and other information with the SEC. This information is available free of charge by calling us collect at (310) 201-4200 or on our website at www.arescapitalcorp.com. The SEC also maintains a website at www.sec.gov that contains this information. The information on the websites referred to herein is not incorporated by reference into this prospectus supplement and the accompanying prospectus.

---

                The underwriters have agreed to purchase the common stock from us at a price of $15.41 per share, which will result in $220,054,800 of proceeds to us before expenses. The underwriters may offer the shares of common stock from time to time for sale in one or more transactions on the NASDAQ Global Select Market, in the over-the-counter market, through negotiated transactions or otherwise at market prices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices.

                The underwriters may also purchase up to an additional 2,142,000 shares of our common stock from us at the price per share set forth above within 30 days of the date of this prospectus supplement.

                Neither the SEC nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

                The shares will be ready for delivery on or about January 25, 2012.

---

Joint Book-Running Managers

The date of this prospectus supplement is January 20, 2012.

---

Table of Contents

              You should rely only on the information contained in this prospectus supplement and the accompanying prospectus. We have not, and the underwriters have not, authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We are not, and the underwriters are not, making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus supplement and the accompanying prospectus is accurate only as of the date on the front cover of this prospectus supplement or such prospectus, as applicable. Our business, financial condition, results of operations and prospects may have changed since that date.

Prospectus Supplement
TABLE OF CONTENTS

Prospectus
TABLE OF CONTENTS

i

---

Table of Contents

ii

---

Table of Contents

FORWARD-LOOKING STATEMENTS

              Some of the statements in this prospectus supplement and the accompanying prospectus constitute forward-looking statements, which relate to future events or our future performance or financial condition. The forward-looking statements contained in this prospectus supplement involve a number of risks and uncertainties, including statements concerning:

•

our, or our portfolio companies', future business, operations, operating results or prospects;



•

the return or impact of current and future investments;



•

the impact of a protracted decline in the liquidity of credit markets on our business;



•

the impact of fluctuations in interest rates on our business;



•

the impact of changes in laws or regulations (including interpretation thereof) governing our operations or the operations of our portfolio companies;



•

the valuation of our investments in portfolio companies, particularly those having no liquid trading market;



•

our ability to successfully integrate our business with the business of Allied Capital Corporation, including rotating out of certain investments acquired in connection therewith;



•

our ability to recover unrealized losses;



•

our ability to successfully invest any capital raised in this offering;



•

market conditions and our ability to access alternative debt markets and additional debt and equity capital;



•

our contractual arrangements and relationships with third parties;



•

Middle East turmoil and the potential for rising energy prices and its impact on the industries in which we invest;



•

the general economy (including inflation and the U.S. budget deficit) and its impact on the industries in which we invest;



•

the uncertainty surrounding the strength of the U.S. economic recovery;



•

United States and European sovereign debt issues;



•

the financial condition of and ability of our current and prospective portfolio companies to achieve their objectives;



•

our expected financings and investments;



•

our ability to successfully integrate any acquisitions;



•

the adequacy of our cash resources and working capital;



•

the timing, form and amount of any dividend distributions;



•

the timing of cash flows, if any, from the operations of our portfolio companies; and



•

the ability of our investment adviser to locate suitable investments for us and to monitor and administer our investments.

              We use words such as "anticipates," "believes," "expects," "intends," "will," "should," "may" and similar expressions to identify forward-looking statements, although not all forward-looking statements include these words. Our actual results and condition could differ materially from those

S-1

---

Table of Contents

implied or expressed in the forward-looking statements for any reason, including the factors set forth in "Risk Factors" in the accompanying prospectus and the other information included in this prospectus supplement or the accompanying prospectus.

              The forward-looking statements included in this prospectus supplement and the accompanying prospectus have been based on information available to us as of their respective dates, and we assume no obligation to update any such forward-looking statements. Although we undertake no obligation to revise or update any forward-looking statements, whether as a result of new information, future events or otherwise, you are advised to consult any additional disclosures that we may make directly to you or through reports that we have filed or in the future may file with the SEC, including annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K.

              The forward-looking statements in this prospectus supplement and the accompanying prospectus are excluded from the safe harbor protection provided by Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act").

S-2

---

Table of Contents

THE COMPANY

              This summary highlights some of the information contained elsewhere in this prospectus supplement and the accompanying prospectus. It is not complete and may not contain all of the information that you may want to consider. You should read carefully the more detailed information set forth under "Risk Factors" in the accompanying prospectus and the other information included in this prospectus supplement and the accompanying prospectus. Except where the context suggests otherwise, the terms "we," "us," "our," "the Company" and "Ares Capital" refer to Ares Capital Corporation and its consolidated subsidiaries; "Ares Capital Management" and "the investment adviser" refer to Ares Capital Management LLC; "Ares Operations" refers to Ares Operations LLC; and "Ares" and "Ares Management" refer to Ares Management LLC and its affiliated companies (other than portfolio companies of its affiliated funds).

              As described in more detail below, we consummated the acquisition (the "Allied Acquisition") of Allied Capital Corporation ("Allied Capital") on April 1, 2010. Other than as set forth in the pro forma financial information or otherwise specifically set forth herein or the accompanying prospectus, financial information presented herein and in the accompanying prospectus for and as of periods ended on or prior to March 31, 2010 does not include any information in respect of Allied Capital. In addition, other than as set forth in the pro forma financial information or otherwise specifically set forth herein or the accompanying prospectus, financial information for the year ended December 31, 2010, including, without limitation, with respect to the Company's consolidated statements of operations, stockholders' equity and cash flows, only includes results attributable to Allied Capital for the period beginning on April 1, 2010.

Ares Capital

              Ares Capital, a Maryland corporation, is a specialty finance company that is a closed-end, non-diversified management investment company. We have elected to be regulated as a business development company, or a "BDC," under the Investment Company Act of 1940, as amended, and the rules and regulations promulgated thereunder, or the "Investment Company Act." We were founded on April 16, 2004, were initially funded on June 23, 2004 and completed our initial public offering on October 8, 2004. We are one of the largest BDCs with approximately $15 billion of total committed capital under management as of December 31, 2011, including available debt capacity (subject to leverage and borrowing base restrictions), vehicles directly or indirectly managed or co-managed by us or one of our wholly owned subsidiaries and vehicles managed or sub-managed by our wholly owned portfolio company, Ivy Hill Asset Management, L.P. ("IHAM").

              We are externally managed by our investment adviser, Ares Capital Management, a wholly owned subsidiary of Ares Management, a global alternative asset manager and a SEC registered investment adviser with approximately $46 billion of total committed capital under management as of December 31, 2011. Ares Operations, our administrator, a wholly owned subsidiary of Ares Management, provides the administrative services necessary for us to operate.

              Our investment objective is to generate both current income and capital appreciation through debt and equity investments. We invest primarily in U.S. middle-market companies, where we believe the supply of primary capital is limited and the investment opportunities are most attractive. However, we may from time to time invest in larger companies. In this prospectus supplement, we generally use the term "middle-market" to refer to companies with annual EBITDA between $10 million and $250 million. As used herein, EBITDA means net income before net interest expense, income tax expense, depreciation and amortization.

              On April 1, 2010, we consummated the Allied Acquisition in an all stock merger whereby each existing share of common stock of Allied Capital was exchanged for 0.325 shares of our common stock. The Allied Acquisition was valued at approximately $908 million as of April 1, 2010. In connection therewith, we issued approximately 58.5 million shares of our common stock to Allied Capital's then-existing stockholders, thereby resulting in our then-existing stockholders owning approximately

S-3

---

Table of Contents

69% of the combined company and the then-existing Allied Capital stockholders owning approximately 31% of the combined company.

              We invest primarily in first and second lien senior loans and mezzanine debt, which in some cases includes an equity component. First and second lien senior loans generally are senior debt instruments that rank ahead of subordinated debt of a given portfolio company. Mezzanine debt is subordinated to senior loans and is generally unsecured. Our investments have generally ranged between $20 million and $250 million each, although the investment sizes may be more or less than this range. Our investment sizes are expected to grow with our capital availability.

              To a lesser extent, we also make preferred and/or common equity investments, which have generally been non-control equity investments of less than $20 million (usually in conjunction with a concurrent debt investment). However, we may increase the size or change the nature of these investments. Also, as a result of the Allied Acquisition, Allied Capital's equity investments, which included equity investments larger than those we have historically made and controlled portfolio company equity investments, became part of our portfolio. We intend to actively seek opportunities over time to dispose of certain of the assets that were acquired in the Allied Acquisition, particularly non-yielding equity investments and controlled portfolio company investments, as well as lower or non-yielding debt investments and investments that may not be core to our investment strategy, and generally rotate them into higher-yielding first and second lien senior loans and mezzanine debt investments. However, there can be no assurance that this strategy will be successful. See "Management's Discussion and Analysis of Financial Condition and Results of Operations—Portfolio and Investment Activity" for further information on the rotation of investments acquired as part of the Allied Acquisition.

              The proportion of these types of investments will change over time given our views on, among other things, the economic and credit environment we are operating in. In connection with our investing activities, we may make commitments with respect to indebtedness or securities of a potential portfolio company substantially in excess of our final investment. In such situations, while we may initially agree to fund up to a certain dollar amount of an investment, we may subsequently syndicate a portion of such amount to third parties, such that we are left with a smaller investment than what was reflected in our original commitment. In addition to originating investments, we may also acquire investments in the secondary market.

              The first and second lien senior loans in which we invest generally have stated terms of three to 10 years and the mezzanine debt investments in which we invest generally have stated terms of up to 10 years, but the expected average life of such first and second lien loans and mezzanine debt is generally between three and seven years. However, we may invest in loans and securities with any maturity or duration. The instruments in which we invest typically are not initially rated by any rating agency, but we believe that if such instruments were rated, they would be below investment grade (rated lower than "Baa3" by Moody's Investors Service, lower than "BBB-" by Fitch Ratings or lower than "BBB-" by Standard & Poor's Ratings Services). We may invest without limit in debt or other securities of any rating, as well as debt or other securities that have not been rated by any nationally recognized statistical rating organization.

              We believe that our investment adviser, Ares Capital Management, is able to leverage the current investment platform, resources and existing relationships with financial sponsors, financial institutions, hedge funds and other investment firms of Ares to provide us with attractive investment opportunities. In addition to deal flow, the Ares investment platform assists our investment adviser in analyzing, structuring and monitoring investments. Ares has been in existence for more than 13 years and its senior principals have an average of over 20 years experience investing in senior loans, high yield bonds, mezzanine debt and private equity securities. The Company has access to the Ares staff of approximately 210 investment professionals and approximately 240 administrative professionals who

S-4

---

Table of Contents

provide assistance in accounting, finance, legal, compliance, operations, information technology and investor relations.

              Since our initial public offering on October 8, 2004 through September 30, 2011, our realized gains have exceeded our realized losses by $155.6 million (excluding the one-time gain on the Allied Acquisition and gains/losses from the extinguishment of debt and other assets). For this same time period, we have exited 167 investments, resulting in an aggregate cash flow realized internal rate of return to us of approximately 16% (based on original cash invested of $4.3 billion and total proceeds from such exits of $5.3 billion). Approximately 77% of the exits resulted in an aggregate cash flow internal rate of return to us of 10% or greater. Internal rate of return is the discount rate that makes the net present value of all cash flows related to a particular investment equal to zero. Internal rate of return is gross of expenses related to investments as these expenses are not allocable to specific investments. Investments are considered to be exited when the original investment objective has been achieved through the receipt of cash and/or non-cash consideration upon the repayment of our debt investment or sale of an investment or through the determination that no further consideration was collectible and, thus, a loss may have been realized. These internal rate of return results are historical results relating to our past performance and are not necessarily indicative of future results, the achievement of which cannot be assured.

              While our primary focus is to generate current income and capital appreciation through investments in first and second lien senior loans and mezzanine debt and, to a lesser extent, equity securities of eligible portfolio companies, we also may invest up to 30% of our portfolio in opportunistic investments in non-qualifying assets, as permitted by the Investment Company Act. See "Regulation" in the accompanying prospectus. Specifically, as part of this 30% basket, we may invest in entities that are not considered "eligible portfolio companies" (as defined in the Investment Company Act), including companies outside of the United States, entities that are operating pursuant to certain exceptions to the Investment Company Act, and publicly traded entities whose public equity market capitalization exceeds the levels provided for in the Investment Company Act.

              We and General Electric Capital Corporation and GE Global Sponsor Finance LLC (collectively, "GE") also co-invest through an unconsolidated vehicle, the Senior Secured Loan Fund LLC, which operates using the name "Senior Secured Loan Program" (the "SSLP"). The SSLP was initially formed in December 2007 to co-invest in "stretch senior" and "unitranche" loans (loans that combine both senior and subordinated debt, generally in a first lien position) of middle-market companies and, as of September 30, 2011, had approximately $5.1 billion of available capital, approximately $3.7 billion in aggregate principal amount of which was funded as of September 30, 2011. At September 30, 2011, we had agreed to make available to the SSLP approximately $1.0 billion, of which approximately $174 million was unfunded. The SSLP is capitalized as transactions are completed and all portfolio decisions and generally all other decisions in respect of the SSLP must be approved by both an affiliate of GE and the Company. See "—Recent Developments" for information regarding an increase in the size of the SSLP subsequent to September 30, 2011.

              We also manage an unconsolidated fund, AGILE Fund I, LLC (the "AGILE Fund"), which had approximately $62 million of total committed capital under management as of December 31, 2011.

              In addition, our portfolio company, IHAM, manages 10 unconsolidated credit vehicles and sub-manages four other unconsolidated credit vehicles (these vehicles managed or sub-managed by IHAM are collectively referred to as the "IHAM Vehicles"), which are described in more detail under "Business—Investments—Managed Vehicles" in the accompanying prospectus. We have also made direct investments in securities of certain of these vehicles. As of December 31, 2011, IHAM had total committed capital under management of approximately $3.4 billion, which included approximately $0.3 billion invested by Ares Capital in IHAM or securities issued by the IHAM Vehicles.

S-5

---

Table of Contents

About Ares

              Founded in 1997, Ares is a global alternative asset manager and SEC registered investment adviser with approximately $46 billion of total committed capital under management and approximately 450 employees as of December 31, 2011.

              Ares specializes in originating and managing assets in both the leveraged finance and private equity markets. Ares' leveraged finance activities include the origination, acquisition and management of senior loans, high yield bonds, mezzanine debt and special situation investments. Ares' private equity activities focus on providing flexible, junior capital to middle-market companies. Ares has the ability to invest across a capital structure, from senior floating rate debt to common equity. This flexibility, combined with Ares' "buy and hold" philosophy, enables Ares to structure an investment to meet the specific needs of a company rather than the less flexible demands of the public markets.

              Ares is comprised of the following groups:

•

Private Debt Group. The Ares Private Debt Group manages Ares Capital, Ares Credit Strategies Fund II, L.P., Ares Credit Strategies Fund III, L.P., Ares Mezzanine Partners, L.P., Ares' private debt middle-market financing business in Europe, Ares Capital Europe ("ACE"), as well as the Ares Commercial Real Estate group, which together had approximately $18.5 billion of total committed capital under management as of December 31, 2011, including capital which may be committed for investment both directly and through certain financial services portfolio companies of the Company. The Ares Private Debt Group focuses primarily on non-syndicated first and second lien senior loans and mezzanine debt, which in some cases may include an equity component. The Ares Private Debt Group also makes equity investments in private middle-market companies, usually in conjunction with a concurrent debt investment.



•

Capital Markets Group. The Ares Capital Markets Group had approximately $22.2 billion of total committed capital under management as of December 31, 2011 through a variety of funds and investment vehicles, focusing primarily on syndicated senior secured loans, high yield bonds, distressed debt, other liquid fixed income investments and other publicly traded debt securities.



•

Private Equity Group. The Ares Private Equity Group had approximately $5.6 billion of total committed capital under management as of December 31, 2011, primarily through Ares Corporate Opportunities Fund L.P., Ares Corporate Opportunities Fund II, L.P. and Ares Corporate Opportunities Fund III, L.P. (collectively referred to as "ACOF"). ACOF generally makes private equity investments in amounts substantially larger than the private equity investments anticipated to be made by Ares Capital. In particular, the Ares Private Equity Group generally focuses on control-oriented equity investments in under-capitalized companies or companies with capital structure issues.

              Ares' senior principals have been working together as a group for many years and have an average of over 20 years of experience in leveraged finance, private equity, distressed debt, investment banking and capital markets. They are backed by a large team of highly disciplined professionals. Ares' rigorous investment approach is based upon an intensive, independent financial analysis, with a focus on preservation of capital, diversification and active portfolio management. These fundamentals underlie Ares' investment strategy and have resulted in large pension funds, banks, insurance companies, endowments and certain high net worth individuals investing in Ares' funds.

Ares Capital Management

              Ares Capital Management, our investment adviser, is served by an origination, investment and portfolio management team of approximately 70 U.S.-based investment professionals led by U.S.-based

S-6

---

Table of Contents

senior partners of the Ares Private Debt Group: Michael Arougheti, Eric Beckman, Kipp deVeer, Mitchell Goldstein and Michael Smith. Ares Capital Management leverages off of Ares' investment platform and benefits from the significant capital markets, trading and research expertise of Ares' investment professionals. Ares has approximately 210 investment professionals covering current investments in more than 1,100 companies across over 30 industries. Ares Capital Management's investment committee has eight members, including senior partners in the Ares Private Debt Group, senior partners in the Ares Private Equity Group and a senior adviser in the Ares Capital Markets Group.

Recent Developments

              In October 2011, Ares Capital and Ares Capital CP Funding LLC ("Ares Capital CP"), a wholly owned subsidiary of Ares Capital, amended the Revolving Funding Facility (as defined herein) to, among other things, increase the commitment size from $400 million to $500 million.

              In October 2011, the total available capital for the Senior Secured Loan Program was increased from $5.1 billion to $7.7 billion. In connection with this increase, GE and Ares Capital agreed to make available to the SSLP up to $6.2 billion and $1.5 billion, respectively.

              From October 1, 2011 through December 31, 2011, we made new investment commitments of $853 million, of which $823 million were funded. Of these new commitments, 55% were in first lien senior secured debt, 30% were in investments in subordinated certificates of the SSLP, 9% were in second lien senior secured debt, 4% were in senior subordinated debt, and 2% were in equity securities. Of the $853 million of new investment commitments, 94% were floating rate, 4% were fixed rate, and 2% were non-interest bearing. The weighted average yield of debt and income producing securities funded during the period at amortized cost was 12.5%. We may seek to syndicate a portion of these new investment commitments to third parties, although there can be no assurance that we will be able to do so.

              From October 1, 2011 through December 31, 2011, we exited $688 million of investment commitments. Of these investment commitments, 78% were in first lien senior secured debt, 7% were in second lien senior secured debt, 5% were in senior subordinated debt, 5% were in collateralized loan obligations, and 5% were in equity and other securities. Of the $688 million of exited investment commitments, 84% were floating rate investments, 7% were on non-accrual status, 5% were fixed rate investments, and 4% were non-interest bearing. The weighted average yield of debt and income producing securities exited or repaid during the period at amortized cost was 9.5%. On the $688 million of investment commitments exited from October 1, 2011 through December 31, 2011, we recognized total net realized losses of approximately $5 million. Included within the $688 million of investment commitments exited from October 1, 2011 through December 31, 2011 were $92 million of investment commitments acquired as part of the Allied Acquisition. We recognized net realized gains of approximately $2 million on the investments exited that were acquired as part of the Allied Acquisition.

              In addition, as of December 31, 2011, we had an investment backlog and pipeline of $170 million and $215 million, respectively. We may syndicate a portion of these investments and commitments to third parties. The consummation of any of the investments in this backlog and pipeline depends upon, among other things: satisfactory completion of our due diligence investigation of the prospective portfolio company, our acceptance of the terms and structure of such investment and the execution and delivery of satisfactory transaction documentation. We cannot assure you that we will make any of these investments or that we will syndicate any portion of such investments and commitments.

              In January 2012, Ares Capital and Ares Capital CP amended the Revolving Funding Facility to, among other things, (i) extend the reinvestment period by one year to January 18, 2015, (ii) extend the

S-7

---

Table of Contents

maturity date by one year to January 18, 2017, and (iii) replace the pricing grid with an applicable spread over LIBOR of 2.50% and an applicable spread over "base rate" of 1.50%.

              Recently, Ares Capital formed Ares Capital JB Funding LLC ("ACJB LLC"), a wholly owned subsidiary of Ares Capital, through which Ares Capital and ACJB LLC have been in negotiations to establish a revolving funding facility (the "New Funding Facility") by entering into a Loan and Servicing Agreement (the "Loan and Servicing Agreement") currently being negotiated with a large international bank. If the transaction is closed as it is currently proposed, the New Funding Facility will allow ACJB LLC to borrow up to $200 million. In connection with the possible New Funding Facility, we expect to enter into a Purchase and Sale Agreement with ACJB LLC pursuant to which we may sell to ACJB LLC certain loans that we have originated or acquired (the "New Loans") from time to time. The obligations of ACJB LLC under the New Funding Facility as proposed will be secured by all of the assets held by ACJB LLC, including the New Loans sold or transferred by Ares Capital to ACJB LLC. It is anticipated that the New Funding Facility will be a revolving funding facility with a three year reinvestment period and an eight year final maturity date and that the reinvestment period and final maturity are both expected to be subject to two one-year extensions by mutual agreement.

              Subject to certain exceptions and as currently proposed, we expect that the interest charged on the New Funding Facility will be based on LIBOR plus 2.125% (with no floor) or a "base rate" (which is the greater of a prime rate and the federal funds rate plus 0.50%) plus 1.125% (with no floor). Neither Ares Capital nor ACJB LLC has entered into the New Funding Facility yet and there can be no assurance that the New Funding Facility will be consummated on the terms described above, if at all. To the extent the New Funding Facility is closed, any borrowings will be subject to leverage and borrowing base restrictions consistent with our other facilities. The foregoing description is a summary only and is qualified by the documents anticipated to be entered into in connection with the New Funding Facility, when, as and if executed by Ares Capital, ACJB LLC and the other parties thereto.

Our Corporate Information

              Our administrative offices are located at 2000 Avenue of the Stars, 12th Floor, Los Angeles, California 90067, telephone number (310) 201-4200, and our executive offices are located at 245 Park Avenue, 44^th Floor, New York, New York 10167, telephone number (212) 750-7300.

S-8

---

Table of Contents

FEES AND EXPENSES

              The following table is intended to assist you in understanding the costs and expenses that an investor in our common stock will bear, directly or indirectly, based on the assumptions set forth below. We caution you that some of the percentages indicated in the table below are estimates and may vary. Except where the context suggests otherwise, whenever this prospectus supplement or the accompanying prospectus contains a reference to fees or expenses paid or to be paid by "you," "us," "the Company" or "Ares Capital," or that "we" will pay fees or expenses, stockholders will directly or indirectly bear such fees or expenses as investors in Ares Capital.

---

(1)

The underwriting discounts and commissions with respect to the shares sold in this offering, which is a one-time fee, is the only sales load paid in connection with this offering. Because the underwriters may offer the shares from time to time, for the purpose of calculating sales load, we have assumed the underwriters will sell the shares to the public at a price of $16.09 per share, our closing price on January 19, 2012.

(2)

Amount reflects estimated offering expenses of approximately $580,000 and based on the 14,280,000 shares offered in this offering (assuming that the underwriters do not exercise their option to purchase additional shares).

(3)

The expenses of the dividend reinvestment plan are included in "Other expenses."

(4)

"Consolidated net assets attributable to common stock" equals our average net assets for the nine months ended September 30, 2011.

(5)

Our management fee is currently 1.5% of our total assets other than cash and cash equivalents (which includes assets purchased with borrowed amounts). For the purposes of this table, we have assumed that we maintain no cash or cash equivalents. The 2.32% reflected on the table is calculated on our average net assets (rather than our total assets). See "Management—Investment Advisory and Management Agreement" in the accompanying prospectus.

(6)

This item represents our investment adviser's incentive fees based on annualizing actual amounts earned on our pre-incentive fee net investment income for the nine months ended September 30, 2011 and assumes that the incentive fees earned at the end of the 2011 calendar year will be based on the actual cumulative realized capital gains computed net of cumulative realized capital losses and unrealized capital depreciation as of September 30, 2011. For purposes of this table, we

S-9

---

Table of Contents

have assumed that this fee will remain constant although it is based on Ares Capital's performance and will not be paid unless Ares Capital achieves certain goals. We expect to invest or otherwise utilize all of the net proceeds from this offering within three months of the date of this offering and may have capital gains and interest income that could result in the payment of an incentive fee to our investment adviser in the first year after completion of this offering. Since our initial public offering through September 30, 2011, the average quarterly incentive fee payable to our investment adviser has been approximately 0.56% of our weighted average net assets (2.24% on an annualized basis). For more detailed information about incentive fees previously incurred by us, please see Note 3 to our consolidated financial statements for the year ended December 31, 2010 and the nine months ended September 30, 2011.


The incentive fee consists of two parts:


The first, payable quarterly in arrears, equals 20% of our pre-incentive fee net investment income (including interest that is accrued but not yet received in cash), subject to a 1.75% quarterly (7.0% annualized) hurdle rate and a "catch-up" provision measured as of the end of each calendar quarter. Under this provision, in any calendar quarter, our investment adviser receives no incentive fee until our net investment income equals the hurdle rate of 1.75% but then receives, as a "catch-up," 100% of our pre-incentive fee net investment income with respect to that portion of such pre-incentive fee net investment income, if any, that exceeds the hurdle rate but is less than 2.1875%. The effect of this provision is that, if pre-incentive fee net investment income exceeds 2.1875% in any calendar quarter, our investment adviser will receive 20% of our pre-incentive fee net investment income as if a hurdle rate did not apply.


The second part (the "Capital Gains Fee"), payable annually in arrears, equals 20% of our realized capital gains on a cumulative basis from inception through the end of the year, if any, computed net of all realized capital losses and unrealized capital depreciation on a cumulative basis, less the aggregate amount of any previously paid capital gain incentive fees.


We will defer cash payment of any incentive fee otherwise earned by our investment adviser if, during the most recent four full calendar quarter period ending on or prior to the date such payment is to be made, the sum of (a) our aggregate distributions to our stockholders and (b) our change in net assets (defined as total assets less indebtedness and before taking into account any incentive fees payable during the period) is less than 7.0% of our net assets (defined as total assets less indebtedness) at the beginning of such period.


These calculations will be adjusted for any share issuances or repurchases.


"Incentive fees payable under investment advisory and management agreement" does not include an accrual (in accordance with GAAP) for a capital gains incentive fee of $28.2 million for the nine months ended September 30, 2011 because no capital gains incentive fee was payable under the investment advisory and management agreement. GAAP requires that the capital gains incentive fee accrual consider the cumulative aggregate unrealized capital appreciation in the calculation, as a capital gains incentive fee would be payable if such unrealized capital appreciation were realized, even though such unrealized capital appreciation is not permitted to be considered in calculating the fee actually payable under the Investment Company Act or the investment advisory and management agreement. This GAAP accrual is calculated using the aggregate cumulative realized capital gains and losses and aggregate cumulative unrealized capital depreciation included in the calculation of the Capital Gains Fee plus the aggregate cumulative unrealized capital appreciation. If such amount is positive at the end of a period, then GAAP requires us to record a capital gains incentive fee equal to 20% of such cumulative amount, less the aggregate amount of actual Capital Gains Fees paid or capital gains incentive fees accrued under GAAP in all prior periods. The resulting accrual for any capital gains incentive fee under GAAP in a given period may result in an additional expense if such cumulative amount is greater

S-10

---

Table of Contents

than in the prior period or a reversal of previously recorded expense if such cumulative amount is less than in the prior period. If such cumulative amount is negative, then there is no accrual. There can be no assurance that such unrealized capital appreciation will be realized in the future or that the amount accrued for will ultimately be paid.


See "Management—Investment Advisory and Management Agreement" in the accompanying prospectus.

(7)

"Interest payments on borrowed funds" represents an estimate of our annualized interest expenses based on actual interest and credit facility expenses incurred for the nine months ended September 30, 2011. During the nine months ended September 30, 2011, our average outstanding borrowings were $1,670.6 million and cash paid for interest expense was $66.1 million. We had outstanding borrowings of $1,899.6 million (with a carrying value of $1,800.2 million) at September 30, 2011. This item is based on our assumption that our borrowings and interest costs after an offering will remain similar to those prior to this offering. The amount of leverage that we employ at any particular time will depend on, among other things, our board of directors' and our investment adviser's assessment of market and other factors at the time of any proposed borrowing. See "Risk Factors—Risks Relating to Our Business—We borrow money, which magnifies the potential for gain or loss on amounts invested and may increase the risk of investing with us" in the accompanying prospectus.

(8)

Includes our overhead expenses, including payments under our administration agreement with Ares Operations, based on our allocable portion of overhead and other expenses incurred by Ares Operations in performing its obligations under the administration agreement, and income taxes. Such expenses are estimates based on annualized "Other expenses" for the nine months ended September 30, 2011. The holders of shares of our common stock (and not the holders of our debt securities or preferred stock, if any) indirectly bear the cost associated with our annual expenses. See "Management—Administration Agreement" in the accompanying prospectus.

(9)

The Company's stockholders indirectly bear the expenses of underlying funds or other investment vehicles that would be investment companies under section 3(a) of the Investment Company Act but for the exceptions to that definition provided for in sections 3(c)(1) and 3(c)(7) of the Investment Company Act ("Acquired Funds") in which the Company invests. This amount includes the fees and expenses of Acquired Funds in which the Company is invested as of September 30, 2011. Certain of these Acquired Funds are subject to management fees, which generally range from 1% to 2.5% of total net assets, or incentive fees, which generally range between 15% to 25% of net profits. When applicable, fees and expenses are based on historic fees and expenses for the Acquired Funds. For those Acquired Funds with little or no operating history, fees and expenses are based on expected fees and expenses stated in the Acquired Funds' offering memorandum, private placement memorandum or other similar communication without giving effect to any performance. Future fees and expenses for these Acquired Funds may be substantially higher or lower because certain fees and expenses are based on the performance of the Acquired Funds, which may fluctuate over time. The amount of the Company's average net assets used in calculating this percentage was based on average monthly net assets of $3.1 billion for the nine months ended September 30, 2011.

(10)

"Total annual expenses" as a percentage of consolidated net assets attributable to common stock are higher than the total annual expenses percentage would be for a company that is not leveraged. We borrow money to leverage and increase our total assets. The SEC requires that the "Total annual expenses" percentage be calculated as a percentage of net assets (defined as total assets less indebtedness and before taking into account any incentive fees payable during the period), rather than the total assets, including assets that have been funded with borrowed monies.

S-11

---

Table of Contents

Example

              The following example demonstrates the projected dollar amount of total cumulative expenses over various periods with respect to a hypothetical investment in our common stock. In calculating the following expense amounts, we have assumed that we would have no additional leverage, that none of our assets are cash or cash equivalents, and that our annual operating expenses would remain at the levels set forth in the table above. Transaction expenses are not included in the following example.

              The foregoing table is to assist you in understanding the various costs and expenses that an investor in our common stock will bear directly or indirectly. While the example assumes, as required by the SEC, a 5% annual return, our performance will vary and may result in a return greater or less than 5%. The incentive fee under the investment advisory and management agreement, which, assuming a 5% annual return, would either not be payable or have an insignificant impact on the expense amounts shown above, is not included in the example. If we achieve sufficient returns on our investments, including through the realization of capital gains, to trigger an incentive fee of a material amount, our expenses, and returns to our investors, would be higher. In addition, while the example assumes reinvestment of all dividends and distributions at net asset value, if our board of directors authorizes and we declare a cash dividend, participants in our dividend reinvestment plan who have not otherwise elected to receive cash will receive a number of shares of our common stock, determined by dividing the total dollar amount of the dividend payable to a participant by the market price per share of our common stock at the close of trading on the valuation date for the dividend. See "Dividend Reinvestment Plan" in the accompanying prospectus for additional information regarding our dividend reinvestment plan.

              This example and the expenses in the table above should not be considered a representation of our future expenses as actual expenses (including the cost of debt, if any, and other expenses) that we may incur in the future and such actual expenses may be greater or less than those shown.

S-12

---

Table of Contents

SELECTED CONDENSED CONSOLIDATED FINANCIAL DATA OF ARES CAPITAL

              The following selected financial and other data as of and for the years ended December 31, 2010, 2009, 2008, 2007 and 2006 are derived from our consolidated financial statements, which have been audited by KPMG LLP, an independent registered public accounting firm whose report thereon is included elsewhere in the accompanying prospectus. The selected financial and other data for the nine months ended September 30, 2011 and 2010 and other quarterly financial information are derived from our unaudited financial statements, but in the opinion of management, reflects all adjustments (consisting only of normal recurring adjustments) that are necessary to present fairly the results of such interim periods. Interim results as of and for the nine months ended September 30, 2011 are not necessarily indicative of the results that may be expected for the year ending December 31, 2011. The data should be read in conjunction with our consolidated financial statements and notes thereto and "Management's Discussion and Analysis of Financial Condition and Results of Operations" and "Senior Securities," which are included elsewhere in this prospectus supplement or the accompanying prospectus.

S-13

---

Table of Contents

ARES CAPITAL CORPORATION AND SUBSIDIARIES
SELECTED FINANCIAL DATA
As of and For the Nine Months Ended September 30, 2011 and 2010 and
As of and For the Years Ended December 31, 2010, 2009, 2008, 2007 and 2006
(dollar amounts in millions, except per share data and as otherwise indicated)

S-14

---

Table of Contents

S-15

---

Table of Contents

SELECTED QUARTERLY DATA (Unaudited)
(dollar amounts in thousands, except per share data)

 

S-16

---

Table of Contents

---

(1)

The Allied Capital equivalent pro forma per share amount is calculated by multiplying the pro forma combined share amounts by the common stock exchange ratio of 0.325.

(2)

The cash dividends declared per share represent the actual dividends declared per share for the period presented. The pro forma combined dividends declared is the dividends per share as declared by Ares Capital.

---

(1)

Net asset value per share is determined as of the last day in the relevant quarter and therefore may not reflect the net asset value per share on the date of the high and low closing sales prices. The net asset values shown are based on outstanding shares at the end of the relevant quarter.

(2)

Calculated as the respective high or low closing sales price divided by net asset value.

(3)

Represents the dividend or distribution declared in the relevant quarter.

*

Net asset value has not yet been calculated for this period.

**

Dividend has not yet been declared for this period.

---

(1)

The above table reflects the carrying value of indebtedness outstanding as of September 30, 2011. As of December 31, 2011, indebtedness under the Revolving Credit Facility and the Revolving Funding Facility was $395.0 million and $463.0 million, respectively. The net proceeds from the sale of our common stock in this offering are expected to be used to pay down outstanding indebtedness under the Revolving Credit Facility or the Revolving Funding Facility. See "Use of Proceeds."