SUMMARY

The following summary highlights some of the information contained in this joint proxy statement/prospectus. This summary may not contain all of the information that is important to you. For a more complete description of the merger agreement, the merger and the other transactions contemplated thereby, Realty Income and ARCT encourage you to read carefully this entire joint proxy statement/prospectus, including the attached Annexes. In addition, Realty Income and ARCT encourage you to read the information incorporated by reference into this joint proxy statement/prospectus, which includes important business and financial information about Realty Income and ARCT that has been filed with the Securities and Exchange Commission, which we refer to as the SEC. You may obtain the information incorporated by reference into this joint proxy statement/prospectus without charge by following the instructions in the section entitled “Where You Can Find More Information; Incorporation by Reference.”

The Companies

Realty Income Corporation

Realty Income is The Monthly Dividend Company^®. Realty Income is a Maryland corporation which is organized to operate as an equity real estate investment trust, commonly referred to as a REIT. Realty Income’s primary business objective is to generate dependable monthly cash distributions from a consistent and predictable level of funds from operations, which we refer to as FFO, per share. Additionally, Realty Income seeks to increase distributions to common stockholders and FFO per share through both active portfolio management and the acquisition of additional properties.

Realty Income is a fully integrated, self-administered real estate company with in-house acquisition, leasing, legal, credit research, real estate research, portfolio management and capital markets expertise. As of June 30, 2012, Realty Income owned a diversified portfolio of 2,762 properties located in 49 states, with over 28.7 million square feet of leasable space leased to 136 different retail and other commercial enterprises doing business in 38 separate industries. Of the 2,762 properties in the portfolio at that date, 2,746, or 99.4%, were single-tenant properties, and the remaining 16 were multi-tenant properties. At June 30, 2012, of the 2,746 single-tenant properties, 2,672, or 97.3%, were leased with a weighted average remaining lease term (excluding rights to extend a lease at the option of the tenant) of approximately 11.1 years.

Realty Income common stock is listed on the New York Stock Exchange, which we refer to as the NYSE, and trades under the symbol “O.”

Realty Income’s principal executive offices are located at 600 La Terraza Boulevard, Escondido, California 92025-3873, and its telephone number is (760) 741-2111.

Tau Acquisition LLC, which we refer to as Merger Sub, is a Delaware limited liability company and a direct wholly owned subsidiary of Realty Income that was formed for the purpose of entering into the merger agreement.

American Realty Capital Trust, Inc.

ARCT is a Maryland corporation incorporated in August 2007 that qualifies as a REIT for federal income tax purposes. ARCT was formed to acquire a diversified portfolio of commercial real estate, which consists primarily of freestanding single tenant properties net leased to credit worthy tenants on a long-term basis. In January 2008, ARCT commenced an initial public offering on a “best efforts” basis to sell up to 150.0 million shares of common stock, excluding 25.0 million shares issuable pursuant to a distribution reinvestment plan, offered at a price of $10.00 per share, subject to certain volume and other discounts, which we refer to as the ARCT IPO. In March 2008, ARCT commenced real estate operations. The ARCT IPO closed in July 2011 and ARCT operated as a non-traded REIT through February 29, 2012.

Effective as of March 1, 2012, ARCT internalized the management services previously provided by American Realty Capital Advisors, LLC and its affiliates, which we refer to as the Internalization, as a result of which ARCT became a self-administered REIT managed full-time by its own management team.

Concurrent with the Internalization, ARCT listed its common stock on the NASDAQ Global Select Market, which we refer to as NASDAQ, and commenced trading under the symbol “ARCT,” and ARCT’s common stock continues to be so listed and trades under such symbol.

Substantially all of ARCT’s business is conducted through American Realty Capital Operating Partnership, L.P., a Delaware limited partnership, which we refer to as the ARCT OP, of which ARCT is the sole general partner.

As of June 30, 2012, ARCT owned 486 properties with 15.6 million square feet of leasable area, 100% leased with a weighted average remaining lease term of 13 years. In constructing the portfolio, ARCT has been committed to diversification by industry, tenant and geography.

ARCT’s principal executive offices are located at 405 Park Avenue, 14^th Floor, New York, New York 10022, and its telephone number is (646) 937-6900.

The Merger and the Merger Agreement

Subject to the terms and conditions of the merger agreement, at the effective time of the merger, ARCT will merge with and into Merger Sub, with Merger Sub surviving the merger as a direct wholly owned subsidiary of Realty Income. In the merger, each share of ARCT common stock issued and outstanding immediately prior to the effective time of the merger will be converted into the right to receive 0.2874 of a share of Realty Income common stock, which we refer to as the merger consideration, as described under “The Merger Agreement—Merger Consideration; Conversion or Cancellation of Shares in the Merger.” Cash will be paid in lieu of any fractional shares.

Based on the closing price of Realty Income common stock on September 28, 2012, the aggregate value of the merger consideration to be received by ARCT stockholders is expected to be approximately $1.9 billion, based on the number of shares of outstanding ARCT common stock on September 28, 2012. The market value of the merger consideration ultimately received by ARCT stockholders will depend on the closing price of Realty Income common stock on the day that the merger is consummated. See “Risk Factors—Risk Factors Relating to the Merger” beginning on page 20. Because the merger consideration is fixed and the market price of shares of Realty Income common stock may fluctuate, ARCT stockholders cannot be sure of the value of the merger consideration they will receive.

A copy of the merger agreement is attached as Annex A to this joint proxy statement/prospectus and is incorporated herein by reference. Realty Income and ARCT encourage you to carefully read the merger agreement in its entirety because it is the principal document governing the merger.

Voting Agreement

Realty Income and ARCT have entered into a voting agreement with Nicholas S. Schorsch and William M. Kahane, which we refer to as the voting agreement. In the voting agreement, each of Messrs. Schorsch and Kahane has agreed to vote all of his shares of ARCT common stock in favor of approval of the merger and the other transactions contemplated by the merger agreement, subject to certain limitations, and to vote against certain actions that would reasonably be expected to impede the merger.

A copy of the voting agreement is attached as Annex B to this joint proxy statement/prospectus and is incorporated herein by reference.

Side Letter

Realty Income has entered into a side letter agreement, which we refer to as the side letter, with AR Capital, LLC, which we refer to as AR Capital, and Mr. Schorsch. In the side letter, each of AR Capital and Mr. Schorsch has agreed, among other things, to (i) reimburse Realty Income for certain transaction expenses of ARCT in excess of $15 million, (ii) indemnify Realty Income and the surviving entity against costs and expenses resulting from the termination of ARCT employees and certain leases and personal property of ARCT and (iii) not purchase certain real properties that are currently contemplated to be purchased by ARCT. AR Capital has also agreed to use commercially reasonable efforts to unwind all joint ventures of ARCT and to waive all fees in connection with the unwinding of certain joint ventures to which ARCT is a party.

A copy of the side letter is attached as Annex C to this joint proxy statement/prospectus and is incorporated herein by reference.

Recommendation of Realty Income’s Board of Directors

Realty Income’s board of directors has unanimously (i) determined that the merger agreement and the merger, including the issuance of Realty Income common stock in connection with the merger, are advisable and in the best interests of Realty Income and its stockholders; (ii) approved the merger agreement, the merger and the other transactions contemplated thereby and (iii) approved the issuance of shares of Realty Income common stock to ARCT stockholders pursuant to the merger agreement.

Realty Income’s board of directors unanimously recommends that Realty Income stockholders vote FOR the proposal to approve the issuance of shares of Realty Income common stock to ARCT stockholders pursuant to the merger agreement FOR the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the issuance of shares of Realty Income common stock to ARCT stockholders pursuant to the merger agreement.

Recommendation of ARCT’s Board of Directors

ARCT’s board of directors has unanimously (i) determined that the merger agreement, the merger and the other transactions contemplated thereby are advisable, fair to, and in the best interests of ARCT and its stockholders, and (ii) approved the merger agreement, the merger and the other transactions contemplated thereby.

ARCT’s board of directors unanimously recommends that ARCT stockholders vote FOR the proposal to approve the merger and the other transactions contemplated by the merger agreement, FOR the proposal to approve, on a non-binding, advisory basis, the compensation that may be paid or become payable to ARCT’s named executive officers in connection with the merger, which we at times refer to as merger-related compensation, and FOR the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the merger and the other transactions contemplated by the merger agreement.

Stockholders Entitled to Vote; Vote Required

Realty Income

Realty Income stockholders who owned shares of Realty Income common stock at the close of business on October 24, 2012, which is referred to as Realty Income’s record date, are entitled to notice of and to vote at Realty Income’s special meeting. On Realty Income’s record date, there were [—] shares of Realty Income common stock outstanding and entitled to vote at Realty Income’s special meeting, held by approximately [—]

holders of record. Each share of Realty Income common stock is entitled to one vote on each proposal to be voted on at Realty Income’s special meeting.

At Realty Income’s special meeting, the presence in person or by proxy of stockholders entitled to cast a majority of all the votes entitled to be cast at such meeting shall constitute a quorum. Abstentions will be counted in determining whether a quorum is present at Realty Income’s special meeting.

Approval of the proposal to approve the issuance of shares of Realty Income common stock to ARCT stockholders pursuant to the merger agreement requires the affirmative vote of at least a majority of the votes cast on the proposal, provided that the total votes cast on the proposal represent at least a majority of the outstanding shares of Realty Income common stock entitled to vote on the proposal. Approval of the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the issuance of shares of Realty Income common stock to ARCT stockholders pursuant to the merger agreement requires the affirmative vote of a majority of the votes cast on such proposal.

See page 40 for a description of the effect of abstentions and broker non-votes with respect to the above proposals.

Your vote is very important. You are encouraged to submit your proxy as promptly as possible. If you do not indicate how your shares of Realty Income common stock should be voted on a matter, the shares of Realty Income common stock represented by your properly executed proxy will be voted as Realty Income’s board of directors recommends and therefore FOR the proposal to approve the issuance of shares of Realty Income common stock to ARCT stockholders pursuant to the merger agreement and FOR the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the issuance of shares of Realty Income common stock to ARCT stockholders pursuant to the merger agreement. If you do not provide voting instructions to your broker or other nominee, your shares of Realty Income common stock will NOT be voted at the meeting and will be considered broker non-votes.

ARCT

ARCT stockholders who owned shares of ARCT common stock at the close of business on October 24, 2012, which is referred to as ARCT’s record date, are entitled to notice of and to vote at ARCT’s special meeting. On ARCT’s record date, there were [—] shares of ARCT common stock outstanding and entitled to vote at ARCT’s special meeting, held by approximately [—] holders of record. Each share of ARCT common stock is entitled to one vote on each proposal to be voted on at ARCT’s special meeting.

At ARCT’s special meeting, the presence in person or by proxy of stockholders entitled to cast a majority of all the votes entitled to be cast at such meeting shall constitute a quorum. Abstentions will be counted in determining whether a quorum is present at ARCT’s special meeting.

Approval of the proposal to approve the merger and the other transactions contemplated by the merger agreement requires the affirmative vote of the holders of at least a majority of the outstanding shares of ARCT common stock entitled to vote on such proposal. The approval of (i) the proposal to approve, on a non-binding, advisory basis, the compensation that may be paid or become payable to ARCT’s named executive officers in connection with the merger and (ii) the proposal to adjourn ARCT’s special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the merger and the other transactions contemplated by the merger agreement in each case the affirmative vote of a majority of the votes cast on such proposal.

See page 44 for a description of the effect of abstentions and broker non-votes with respect to the above proposals.

Your vote is very important. You are encouraged to submit your proxy as promptly as possible. If you do not indicate how your shares of ARCT common stock should be voted on a matter, the shares of ARCT common stock represented by your properly executed proxy will be voted as ARCT’s board of directors recommends and therefore FOR the proposal to approve the merger and the other transactions contemplated by the merger agreement, FOR the proposal to approve, on a non-binding advisory basis, the compensation that may be paid or become payable to ARCT’s named executive officers in connection with the merger, and FOR the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the merger and the other transactions contemplated by the merger agreement. If you do not provide voting instructions to your broker or other nominee, your shares of ARCT common stock will NOT be voted at the meeting and will be considered broker non-votes.

Opinions of Financial Advisors

Opinions of Realty Income’s Financial Advisors

BofA Merrill Lynch. In connection with the merger, Merrill Lynch, Pierce, Fenner & Smith Incorporated, which we refer to as BofA Merrill Lynch, one of Realty Income’s financial advisors, delivered to Realty Income’s board of directors a written opinion, dated September 5, 2012, as to the fairness, from a financial point of view and as of the date of the opinion, to Realty Income of the exchange ratio provided for in the merger. The full text of the written opinion, dated September 5, 2012, of BofA Merrill Lynch, which describes, among other things, the assumptions made, procedures followed, factors considered and limitations on the review undertaken, is attached as Annex D to this document and is incorporated by reference herein in its entirety. BofA Merrill Lynch provided its opinion to Realty Income’s board of directors (in its capacity as such) for the benefit and use of Realty Income’s board of directors in connection with and for purposes of its evaluation of the exchange ratio from a financial point of view. BofA Merrill Lynch’s opinion does not address any other aspect of the merger and no opinion or view was expressed as to the relative merits of the merger in comparison to other strategies or transactions that might be available to Realty Income or in which Realty Income might engage or as to the underlying business decision of Realty Income to proceed with or effect the merger. BofA Merrill Lynch’s opinion does not address any other aspect of the merger and does not constitute a recommendation to any stockholder as to how to vote or act in connection with the proposed merger or any related matter.

Wells Fargo Securities, LLC. In connection with the merger, Realty Income’s board of directors received an opinion, dated September 5, 2012, of Wells Fargo Securities, LLC, one of Realty Income’s financial advisors, which we refer to as Wells Fargo Securities, as to the fairness, from a financial point of view and as of the date of such opinion, to Realty Income of the exchange ratio provided for in the merger pursuant to the merger agreement. The full text of the written opinion is attached as Annex E to this joint proxy statement/prospectus and is incorporated herein by reference. The written opinion sets forth, among other things, the assumptions made, procedures followed, factors considered and limitations on the review undertaken by Wells Fargo Securities in rendering its opinion. The opinion was addressed to Realty Income’s board of directors (in its capacity as such) for its information and use in connection with its evaluation of the exchange ratio from a financial point of view to Realty Income and Wells Fargo Securities expressed no opinion or view with regard to any other terms, aspects or implications of the merger. Wells Fargo Securities’ opinion did not address the merits of the underlying decision by Realty Income to enter into the merger agreement or the relative merits of the merger compared with other business strategies or transactions available or that have been or might be considered by Realty Income’s management or board of directors or in which Realty Income might engage. The opinion does not constitute a recommendation to Realty Income’s board of directors or any other person or entity in respect of the merger, including as to how any stockholder should vote or act in connection with the merger or any other matters.

See “The Merger—Opinions of Realty Income’s Financial Advisors” beginning on page 67.

Opinion of ARCT’s Financial Advisor

On September 6, 2012, at a meeting of the ARCT board of directors, Goldman, Sachs & Co., which we refer to as Goldman Sachs, rendered to the board of directors of ARCT its oral opinion, subsequently confirmed in writing, that, as of September 6, 2012, and based upon and subject to the limitations and assumptions set forth therein, the exchange ratio of 0.2874 shares of Realty Income common stock to be paid for each share of ARCT common stock pursuant to the merger agreement was fair from a financial point of view to the holders (other than Realty Income and its affiliates) of shares of ARCT common stock.

The full text of the written opinion of Goldman Sachs, dated September 6, 2012, which sets forth the assumptions made, procedures followed, matters considered, qualifications and limitations on the review undertaken in connection with the opinion, is attached to this joint proxy statement/prospectus as Annex F. The summary of the Goldman Sachs opinion provided in this joint proxy statement/prospectus is qualified in its entirety by reference to the full text of the written opinion. Goldman Sachs’ advisory services and opinion were provided for the information and assistance of the board of directors of ARCT in connection with its consideration of the proposed merger and the opinion does not constitute a recommendation as to how any holder of shares of ARCT common stock should vote with respect to the proposed merger or any other matter.

See “The Merger—Opinion of ARCT’s Financial Advisor” beginning on page 84.

Treatment of ARCT Stock Options, Restricted Shares and LTIP Units

Treatment of Stock Options. Pursuant to, and as further described in the merger agreement, each option to purchase ARCT common stock that is outstanding and unexercised at the effective time of the merger will be deemed subject to a cashless exercise and the holder of such option will be deemed to receive a number of shares of ARCT common stock equal to (i) the number of shares of ARCT common stock subject to such option, less (ii) the number of shares of ARCT common stock equal in value to the aggregate exercise price of such option, assuming a fair market value of a share of ARCT common stock equal to the closing price of ARCT common stock on the last completed trading day immediately prior to the consummation of the merger, which shares of ARCT common stock will be converted into the right to receive the merger consideration.

Treatment of Restricted Shares. Pursuant to, and as further described in the merger agreement, each share of ARCT restricted stock outstanding as of immediately prior to the effective time of the merger will become fully vested and will convert into the right to receive the merger consideration.

Treatment of LTIP Units. Pursuant to, and as further described in the merger agreement, each award of long term incentive plan units in ARCT OP, which we refer to as LTIP Units, that is outstanding at the effective time of the merger will become fully vested immediately prior to the merger and will be adjusted as set forth in the merger agreement.

See “The Merger Agreement—Merger Consideration; Conversion or Cancellation of Shares in the Merger—Treatment of ARCT Stock Options, Restricted Shares and LTIP Units” beginning on page 127.

Directors and Management of Realty Income After the Merger

Realty Income currently anticipates that the directors and officers of Realty Income prior to the merger will continue as directors and officers of Realty Income after the merger.

Share Ownership of Directors and Executive Officers of Realty Income

At the close of business on September 28, 2012, the directors and executive officers of Realty Income and their affiliates held and were entitled to vote 1,447,290 shares of Realty Income common stock, collectively representing approximately 1.1% of the shares of Realty Income common stock outstanding and entitled to vote on that date. The directors and executive officers of Realty Income have each indicated that they expect to vote FOR the proposal to approve the issuance of Realty Income common stock to ARCT stockholders pursuant to the merger agreement and FOR the proposal to adjourn the special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the issuance of shares of Realty Income common stock to ARCT stockholders pursuant to the merger agreement.

Share Ownership of Directors and Executive Officers of ARCT

At the close of business on September 28, 2012, the directors and executive officers of ARCT and their affiliates held and were entitled to vote 1,467,136 shares of ARCT common stock, collectively representing approximately 0.93% of the shares of ARCT common stock outstanding and entitled to vote on that date. The directors and executive officers of ARCT have each indicated that they expect to vote FOR the proposal to approve the merger and the other transactions contemplated by the merger agreement, FOR the proposal to approve, on a non-binding, advisory basis, the compensation that may be paid or become payable to ARCT’s named executive officers in connection with the merger, and FOR the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the merger and the other transactions contemplated by the merger agreement. In addition, under the terms of the voting agreement, each of Messrs. Schorsch and Kahane has agreed to vote all of his shares of ARCT common stock in favor of approval of the merger and the other transactions contemplated by the merger agreement, subject to certain limitations.

Interests of ARCT’s Directors and Executive Officers in the Merger

In considering the recommendation of ARCT’s board of directors to approve the merger and the other transactions contemplated by the merger agreement, ARCT stockholders should be aware that ARCT’s directors and executive officers have certain interests in the merger that may be different from, or in addition to, the interests of ARCT stockholders generally. These interests include those discussed below.

In connection with the merger, ARCT and the ARCT OP (acting through and at the direction of ARCT’s independent directors) and AR Capital, an entity majority-owned and controlled by Nicholas S. Schorsch, chairman of the board of directors of ARCT, and William M. Kahane, ARCT’s chief executive officer, president and a director, entered into an Incentive Listing Fee Note Agreement, dated as of September 6, 2012, by and among ARCT, ARCT OP, and AR Capital, as amended by a First Amendment to Incentive Listing Fee Note Agreement on September 10, 2012 which, as amended, we refer to as the Incentive Listing Fee Note Agreement, and a letter agreement, dated September 6, 2012, between Realty Income and AR Capital, pursuant to which the parties agreed to modify the terms of the Subordinated Incentive Listing Fee Note (as defined below), if and to the extent issued, to (i) add a cap of $76,000,000 on its principal amount, (ii) add a floor of $58,600,000 on its principal amount, (iii) provide that, until October 31, 2012, such note shall be due and payable upon demand on not less than five (5) business days’ prior written notice by AR Capital and (iv) eliminate AR Capital’s right to convert the principal amount of the Subordinated Incentive Listing Fee Note into shares of ARCT’s common stock at maturity based on the volume-weighted average of the daily volume-weighted average price, as reported by Bloomberg Financial, increased by the cumulative ARCT dividends paid during the measurement period for each day following the ex-dividend date of each respective dividend on September 5, 2012 and October 3, 2012, as declared by NASDAQ, of the shares issued and outstanding at the Listing, as described below, over the 30 trading days beginning 180 days after the Listing (which measurement period commenced August 28, 2012 and ends October 9, 2012).

In connection with the merger, on September 5, 2012, ARCT entered into a letter agreement, which we refer to as the letter agreement, with Realty Capital Securities, LLC, which we refer to as RC Securities, and ARC Advisory Services, LLC, which we refer to as ARC Advisory Services, to act as non-exclusive financial advisor and information agent, respectively, to ARCT in connection with the merger and the related proxy solicitation seeking approval of the merger by ARCT’s stockholders and to pay an aggregate amount of $1,500,000 in consideration for the services provided under the letter agreement and such fee will be payable upon the closing of the merger; provided that if the merger is not consummated, ARCT will be responsible for the payment of such fee. The letter agreement is subject to the expense cap under the terms of the side letter. See “Side Letter” on page 145 and “The Merger—Interests of ARCT’s Directors and Executive Officers in the Merger—Letter Agreement” on page 97.

In connection with the merger, on September 5, 2012, ARCT and the ARCT OP entered into a certain Legal Services Agreement, which we refer to as the Legal Services Agreement, with ARC Advisory Services, pursuant to which ARCT, on its own behalf and, as general partner of the ARCT OP, on behalf of the ARCT OP, retained ARC Advisory Services to perform legal support services in connection with the merger agreement. ARCT and the ARCT OP will pay to ARC Advisory Services an aggregate amount of $350,000 in consideration for the services provided under the Legal Services Agreement; provided that if the merger does not occur, ARCT will be responsible for the payment of such fee. The Legal Services Agreement is subject to the expense cap under the terms of the side letter. See “Side Letter” on page 145 and “The Merger—Interests of ARCT’s Directors and Executive Officers in the Merger—Legal Services Agreement” on page 98.

In connection with the merger, on September 5, 2012, ARCT and the ARCT OP entered into a certain Legal Services Reimbursement Agreement, which we refer to as the Legal Services Reimbursement Agreement, with ARC Advisory Services, pursuant to which ARCT, on its own behalf and, as general partner of the ARCT OP, on behalf of the ARCT OP, reaffirmed the retention of ARC Advisory Services for the performance of legal support services in connection with the merger agreement rendered prior to the date of the Legal Services Reimbursement Agreement. ARCT and the ARCT OP will pay to ARC Advisory Services an aggregate amount of $1,200,000 in consideration for the services provided under the Legal Services Reimbursement Agreement. The Legal Services Reimbursement Agreement is subject to the expense cap under the terms of the side letter. See “Side Letter” on page 145 and “The Merger—Interests of ARCT’s Directors and Executive Officers in the Merger—Legal Services Reimbursement Agreement” on page 98.

In connection with the merger, on September 5, 2012, ARCT and the ARCT OP entered into a certain Transition Services Agreement, which we refer to as the Transition Services Agreement, with ARC Advisory Services, pursuant to which ARC Advisory Services and ARCT, on its own behalf and, as general partner of the ARCT OP, on behalf of the ARCT OP, memorialized ARC Advisory Services’ obligation to perform the following services, which it has historically performed for, and for which it has historically been compensated by, ARCT and the ARCT OP: legal support, accounting support, marketing support, acquisition support, investor relations support, public relations support, event coordination, human resources and administration, general human resources duties, payroll services, benefits services, insurance and risk management, information technology services, telecom and internet services and services relating to office supplies. The Transition Services Agreement does not govern any legal support services rendered in connection with the merger agreement and its related transactions, which will be governed by the Legal Services Agreement and the Legal Services Reimbursement Agreement. ARCT and the ARCT OP will pay to ARC Advisory Services the actual costs and expenses incurred by ARC Advisory Services in connection with providing the services contemplated by the Transition Services Agreement. See “The Merger—Interests of ARCT’s Directors and Executive Officers in the Merger—Transition Services Agreement” on page 99.

Some of the directors and executive officers of ARCT are entitled to certain contractual “change of control” payments, benefits and incentive awards in connection with the merger.

See “The Merger—Recommendation of ARCT’s Board of Directors and Its Reasons for the Merger” and “The Merger—Interests of ARCT’s Directors and Executive Officers in the Merger.”

Listing of Shares of Realty Income Common Stock; Delisting and Deregistration of Shares of ARCT Common Stock

Approval of the listing on the NYSE of the shares of Realty Income common stock to be issued to ARCT stockholders pursuant to the merger agreement, subject to official notice of issuance, is a condition to each party’s obligation to complete the merger. Realty Income has agreed to use its reasonable best efforts to cause the shares of Realty Income common stock to be issued to ARCT stockholders pursuant to the merger agreement to be approved for listing on the NYSE prior to the effective time of the merger, subject to official notice of issuance. If the merger is completed, shares of ARCT common stock will be delisted from NASDAQ and deregistered under the Securities Exchange Act of 1934, as amended, which we refer to as the Exchange Act.

No Stockholder Appraisal Rights in the Merger

Under the Maryland General Corporation Law, neither Realty Income stockholders nor ARCT stockholders are entitled to exercise appraisal rights in connection with the merger. See “No Appraisal Rights” beginning on page 145.

Conditions to Completion of the Merger

A number of conditions must be satisfied or waived, where legally permissible, before the merger can be consummated. These include, among others:

Neither Realty Income nor ARCT can give any assurance as to when or if all of the conditions to the consummation of the merger will be satisfied or waived or that the merger will occur.

For more information regarding the conditions to the consummation of the merger and a complete list of such conditions, see “The Merger Agreement—Conditions to Completion of the Merger” beginning on page 130.

Regulatory Approvals Required for the Merger

The merger may be subject to the regulatory requirements of municipal, state and federal, domestic or foreign, governmental agencies and authorities. Nevertheless, neither Realty Income nor ARCT is aware of any regulatory approvals that are expected to prevent the consummation of the merger. See “The Merger—Regulatory Approvals Required for the Merger” beginning on page 106.

No Solicitation and Change in Recommendation

Under the merger agreement, ARCT has agreed not to, and to cause its subsidiaries not to (and not authorize and use reasonable best efforts to cause its officers, directors, managers and other representatives not to), directly or indirectly, (i) solicit, initiate, knowingly encourage or facilitate any inquiry, discussion, offer or request that constitutes, or could reasonably be expected to lead to, a competing acquisition proposal, (ii) engage in any discussions or negotiations regarding, or furnish to any third party any nonpublic information in connection with, or knowingly facilitate in any way any effort by, any third party in furtherance of any competing acquisition proposal or inquiry, (iii) approve or recommend a competing acquisition proposal, or enter into any letter of intent, memorandum of understanding, agreement in principle, acquisition agreement, merger agreement, share purchase agreement, asset purchase agreement, share exchange agreement, option agreement or other similar definitive agreement providing for or relating to a competing acquisition proposal, or (iv) propose or agree to do any of the foregoing.

However, prior to the approval of the merger and the other transactions contemplated by the merger agreement by ARCT stockholders, ARCT may, under certain specified circumstances, engage in discussions or negotiations with and provide nonpublic information regarding itself to a third party making an unsolicited, bona fide written competing acquisition proposal. Under the merger agreement, ARCT is required to notify Realty Income promptly if it receives any competing acquisition proposal or inquiry or any request for nonpublic information in connection with a competing acquisition proposal.

Before the approval of the merger and the other transactions contemplated by the merger agreement by ARCT stockholders, ARCT’s board of directors may, under certain specified circumstances, withdraw its recommendation of the merger if ARCT’s board of directors determines in good faith, after consultation with outside legal counsel, that failure to take such action would be inconsistent with the directors’ duties under applicable law. For more information regarding the limitations on ARCT and its board of directors to consider other proposals, see “The Merger Agreement—Covenants and Agreements—No Solicitation of Transactions by ARCT” beginning on page 135.

Termination of the Merger Agreement

Realty Income and ARCT may mutually agree to terminate the merger agreement before completing the merger, even after approval of the Realty Income stockholders or approval of the ARCT stockholders.

In addition, either Realty Income or ARCT (so long as it is not at fault) may decide to terminate the merger agreement if:

ARCT may also terminate the merger agreement prior to the ARCT stockholder approval in order to enter into an alternative acquisition agreement with respect to a superior proposal provided that ARCT concurrently pays the termination fee. Realty Income may also terminate the merger agreement if (i) the ARCT board of directors has made an adverse recommendation change, (ii) ARCT materially breaches its obligations regarding the preparation of the Form S-4 and the joint proxy statement/prospectus and the holding of ARCT’s stockholder meeting, or (iii) ARCT enters into a definitive agreement with respect to an alternative acquisition proposal. For more information regarding the rights of Realty Income and ARCT to terminate the merger agreement, see “The Merger Agreement—Termination of the Merger Agreement” beginning on page 141.

Expenses and Termination Fees

Generally, all fees and expenses incurred in connection with the merger and the transactions contemplated by the merger agreement will be paid by the party incurring those expenses. However, under the side letter, AR Capital and Mr. Schorsch have agreed to reimburse Realty Income for certain transaction expenses of ARCT in excess of $15 million. In addition, the merger agreement provides that if the merger agreement is terminated under certain circumstances, ARCT may be obligated to pay Realty Income a termination fee of $51 million plus $4 million in expense reimbursement. In certain other circumstances, Realty Income or ARCT may be required to pay $4 million in expense reimbursement to the other party, even if, in the case of payment by ARCT, the termination fee is not payable.

For more information regarding the termination fee and expense reimbursement, see “The Merger Agreement—Termination of the Merger Agreement—Termination Fee and Expenses Payable by ARCT to Realty Income” beginning on page 142 and “The Merger Agreement—Termination of the Agreement—Expenses Payable by Realty Income to ARCT” beginning on page 143.

Material U.S. Federal Income Tax Consequences of the Merger

It is expected that the merger will qualify as a reorganization within the meaning of Section 368(a) of the Code, and it is a condition to the completion of the merger that Realty Income and ARCT receive written opinions from their respective counsel to the effect that the merger will be treated as a reorganization within the meaning of Section 368(a) of the Code. Assuming the merger qualifies as such a reorganization, U.S. holders of ARCT common stock generally will not recognize gain or loss for U.S. federal income tax purposes upon the exchange of their ARCT common stock for Realty Income common stock pursuant to the merger, except with respect to cash received in lieu of fractional shares of Realty Income common stock.

For further discussion of the material U.S. federal income tax consequences of the merger, see “Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 106.

Holders of ARCT common stock should consult their tax advisors to determine the tax consequences to them (including the application and effect of any state, local or non-U.S. income and other tax laws) of the merger.

Accounting Treatment of the Merger

Realty Income will account for the merger using the purchase method of accounting under U.S. generally accepted accounting principles, which we refer to as GAAP. The merger will be accounted for by applying the purchase method, with Realty Income treated as the acquiror.

Comparison of Rights of Realty Income Stockholders and ARCT Stockholders

At the effective time of the merger, ARCT stockholders will become Realty Income stockholders. Realty Income’s charter and bylaws contain provisions that are different from ARCT’s charter and bylaws as currently in effect.

For a summary of certain differences between the rights of Realty Income stockholders and ARCT stockholders, see “Comparison of Rights of Realty Income Stockholders and ARCT Stockholders” beginning on page 146.

Recent Developments

During the first six months of 2012, Realty Income acquired properties with an aggregate purchase price of approximately $222 million. From July 1, 2012 through September 27, 2012, Realty Income has acquired properties with an aggregate purchase price of approximately $495 million. Moreover, in addition to the transactions contemplated by the merger agreement, Realty Income has entered into agreements to acquire additional properties with an aggregate purchase price of approximately $284 million. The total purchase price for properties already acquired from July 1, 2012 through September 27, 2012, and the properties that are under contract to be acquired, are approximately $779 million. The total acquired properties and contracted property acquisitions for the second half of 2012 consist of approximately 145 single-tenant properties net leased to 26 different tenants, and all are of property types that Realty Income already has in its portfolio. In aggregate, during all of 2012, Realty Income anticipates acquiring in excess of $1.0 billion of new properties. On an aggregate basis, no single tenant of the properties that Realty Income has acquired or anticipates acquiring during 2012 will account for more than 10% of Realty Income’s assets as of December 31, 2011, which is the date of the last audited balance sheet.

Similarly, ARCT has acquired or entered into agreements to acquire properties with an aggregate purchase price of approximately $78 million during the second half of 2012 and first half of 2013. These acquisitions consist of approximately 40 single-tenant properties net leased to 12 different tenants, and all are in industries and of property types that ARCT already has in its portfolio. On an aggregate basis, no single tenant of the properties that ARCT has acquired or anticipates acquiring during 2012 and the first half of 2013 will account for more than 10% of ARCT’s assets as of December 31, 2011, which is the date of ARCT’s last audited balance sheet.

The acquisitions that have not closed yet are subject to various customary conditions to closing, the failure of which could delay the closing of one or more of these proposed acquisitions or result in one or more of these proposed transactions not closing or closing on terms that are different from those currently contemplated. Realty Income expects to fund any of these acquisitions that close in the future (including any ARCT acquisitions that close after the merger) with borrowings under its acquisition credit facility or possible issuances of additional securities. ARCT is expected to fund any of its acquisitions that are to close before the merger closes with borrowings under its credit facility.

Selected Historical Financial Information of Realty Income

Presented below is the selected consolidated financial data of Realty Income as of and for the periods indicated. The selected historical consolidated financial data as of December 31, 2011 and 2010 and for each of

the fiscal years ended December 31, 2011, 2010 and 2009 have been derived from Realty Income’s historical audited consolidated financial statements, which were adjusted for discontinued operations and are incorporated by reference herein. The selected historical consolidated financial data as of December 31, 2009, 2008 and 2007 and for each of the fiscal years ended December 31, 2008 and 2007 were derived from Realty Income’s historical audited consolidated financial statements, which were adjusted for discontinued operations but not included in this joint proxy statement/prospectus or incorporated by reference herein.

The historical financial data as of June 30, 2012 and 2011 and for the six-month periods ended June 30, 2012 and 2011 were derived from Realty Income’s historical unaudited condensed consolidated financial statements, which are incorporated by reference herein. In Realty Income’s opinion, such unaudited financial statements include all adjustments (consisting of normal recurring adjustments) necessary for a fair presentation of the interim June 30, 2012 financial information. Interim results for the six months ended and as of June 30, 2012 are not necessarily indicative of, and are not projections for, the results to be expected for the fiscal year ending December 31, 2012.

You should read this selected historical financial information together with the financial statements included in reports that are incorporated by reference in this document and their accompanying notes and management’s discussion and analysis of operations and financial condition of Realty Income contained in such reports.

Selected Historical Financial Information of ARCT

The following selected historical financial information for each of the years during the three-year period ended December 31, 2011 and the selected balance sheet data as of December 31, 2011 and 2010 have been derived from ARCT’s audited consolidated financial statements contained in its Annual Report on Form 10-K/A filed with the SEC on May 11, 2012, which has been incorporated into this document by reference. The selected historical financial information for each of the years ended December 31, 2008 and 2007 and as of December 31, 2009, 2008 and 2007 has been derived from ARCT’s audited consolidated financial statements for such years, which have not been incorporated into this document by reference.

The selected historical financial information for each of the six-month periods ended June 30, 2012 and 2011, and as of June 30, 2012 has been derived from ARCT’s unaudited consolidated financial statements contained in ARCT’s Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2012, which has been incorporated into this joint proxy statement/prospectus by reference. The selected historical financial information as of June 30, 2011 has been derived from ARCT’s unaudited consolidated financial statements contained in ARCT’s Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2011, which has not been incorporated into this joint proxy statement/prospectus by reference. In ARCT’s opinion, such unaudited financial statements include all adjustments (consisting of normal recurring adjustments) necessary for a fair presentation of the interim June 30, 2012 financial information. Interim results for the six months ended and as of June 30, 2012 are not necessarily indicative of, and are not projections for, the results to be expected for the fiscal year ending December 31, 2012.

You should read this selected historical financial information together with the financial statements included in reports that are incorporated by reference in this document and their accompanying notes and management’s discussion and analysis of operations and financial condition of ARCT contained in such reports.

Selected Unaudited Pro Forma Consolidated Financial Information

The following tables set forth selected unaudited pro forma consolidated financial information. The pro forma consolidated financial information combines the historical financial statements of Realty Income and ARCT after giving effect to the merger using the purchase method of accounting and Realty Income’s preliminary estimates, assumptions and pro forma adjustments as described below and in the accompanying notes to the unaudited pro forma consolidated financial information.

The unaudited pro forma consolidated financial information should be read in conjunction with Realty Income’s historical consolidated financial statements and ARCT’s historical consolidated financial statements, including the notes thereto, which are incorporated by reference into this proxy statement/prospectus. The selected unaudited pro forma consolidated financial information has been derived from and should be read in conjunction with the unaudited pro forma consolidated financial information and accompanying notes included in this joint proxy statement/prospectus beginning on page F-1.

The unaudited pro forma consolidated financial information is presented for illustrative purposes only and does not purport to be indicative of the results that would actually have occurred if the transactions described above had occurred as presented in such statements or that may be obtained in the future. In addition, future results may vary significantly from the results reflected in such statements.