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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

SCHEDULE 14A

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934

 

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To the Shareholders of Select Income REIT:

        Notice is hereby given that the annual meeting of shareholders of Select Income REIT, a Maryland real estate investment trust, will be held at 9:30 a.m., local time, on Monday, May 13, 2013, at Two Newton Place, 255 Washington Street, Suite 100, Newton, Massachusetts 02458 for the following purposes:

1.

To elect the nominee named in our proxy statement to our Board of Trustees as the Independent Trustee in Class I ("proposal 1").



2.

To elect the nominee named in our proxy statement to our Board of Trustees as the Managing Trustee in Class I ("proposal 2").



3.

To ratify the appointment of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2013 ("proposal 3").



4.

To consider and vote upon such other matters as may properly come before the meeting and at any adjournments or postponements thereof.

        OUR BOARD OF TRUSTEES UNANIMOUSLY RECOMMENDS THAT YOU VOTE "FOR" THE NOMINEES FOR TRUSTEE IN PROPOSALS 1 AND 2 AND "FOR" PROPOSAL 3.

        We encourage you to contact the firm assisting us in the solicitation of proxies, Innisfree M&A Incorporated, or Innisfree, if you have any questions or need assistance in voting your shares. Banks and brokers may call Innisfree, collect, at (212) 750-5833. Shareholders may call Innisfree, toll-free, at (877) 717-3922.

        Shareholders of record at the close of business on February 19, 2013, are entitled to notice of, and to vote at, the meeting and at any adjournment or postponement thereof.

        Securities and Exchange Commission rules allow us to furnish proxy materials to our shareholders on the internet. You can now access proxy materials and authorize a proxy to vote your shares at www.proxyvote.com. You may also authorize a proxy to vote your shares over the internet or by telephone by following the instructions on that website. In order to vote over the internet or by telephone you must have your shareholder identification number, which is set forth in the Notice Regarding the Availability of Proxy Materials mailed to you. If your shares are held in the name of a brokerage firm, bank, nominee or other institution, you should provide instructions to your broker, bank, nominee or other institution on how to vote your shares. You may also request a paper proxy card to submit your vote by mail. If you attend the meeting and vote in person, that vote will revoke any proxy you previously submitted. If you hold shares in the name of a brokerage firm, bank, nominee or other institution, you must provide a legal proxy from that institution in order to vote your shares at the meeting. Whether or not you plan to attend the meeting, please read the proxy statement and complete or authorize a proxy for your shares as soon as possible. Your vote is important, no matter how many or how few shares you own.

Newton, Massachusetts
February 25, 2013

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SELECT INCOME REIT
Two Newton Place
255 Washington Street, Suite 300
Newton, Massachusetts 02458

PROXY STATEMENT
FOR THE
ANNUAL MEETING OF SHAREHOLDERS
To be held at 9:30 a.m. on Monday, May 13, 2013
at
Two Newton Place
255 Washington Street, Suite 100
Newton, Massachusetts 02458

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INTRODUCTION

        A notice of the annual meeting of shareholders of Select Income REIT, a Maryland real estate investment trust, or the Company, is on the preceding page and a form of proxy solicited by our Board of Trustees, or our Board, accompanies this proxy statement. This proxy statement and a form of proxy, together with our annual report to shareholders for the year ended December 31, 2012, are first being made available, and a Notice Regarding the Availability of Proxy Materials, or the Notice of Internet Availability, is first being mailed, to shareholders on or about February 25, 2013.

        The annual meeting record date is February 19, 2013. Only shareholders of record at the close of business on February 19, 2013, are entitled to notice of, and to vote at, the meeting and at any postponement or adjournment thereof. We had 39,282,592 common shares of beneficial interest, $.01 par value per share, or common shares, outstanding on the record date and entitled to vote at the meeting. Our common shares are listed on the New York Stock Exchange, or NYSE. The holders of our outstanding common shares are entitled to one vote per common share.

        A quorum of shareholders is required for shareholders to take action at the meeting. The presence, in person or by proxy, of holders of common shares entitled to cast a majority of all the votes entitled to be cast at the meeting shall constitute a quorum. Common shares represented by valid proxies will count for the purpose of determining the presence of a quorum for the meeting. Abstentions and broker non-votes, if any, will be treated as shares present for purposes of determining whether a quorum is present. Failure of a quorum to be present at the meeting will necessitate adjournment of the meeting and will subject us to additional expense. Under our bylaws, the chairperson of the meeting may adjourn the meeting if less than a quorum is present at the meeting.

        The nominees for election as Trustees described in proposals 1 and 2 will be elected if they receive a plurality of all the votes cast. The affirmative vote of a majority of the votes cast will be necessary to ratify the appointment of Ernst & Young LLP as our independent registered public accounting firm in proposal 3. Proposal 3 is a nonbinding shareholder advisory vote and, if approved, would serve only as a recommendation to our Board.

        The individuals named as proxies on a properly completed proxy will vote in accordance with your directions as indicated thereon. If you properly complete your proxy and give no voting instructions, your shares will be voted "FOR" the nominees for Trustee in proposals 1 and 2 and "FOR" proposal 3.

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        Shareholders of record may authorize a proxy to vote their shares over the internet or by telephone in the manner provided on the website indicated in the Notice of Internet Availability mailed to them, or, if they requested and received paper or email copies of proxy materials, by completing and returning the proxy card or by attending the meeting and voting in person. Proxies submitted by mail, over the internet or by telephone must be received by 11:59 p.m. Eastern Time on Sunday, May 12, 2013.

        Broker non-votes occur in respect of shares held in street name when the broker indicates that voting instructions for a particular matter have not been received from the beneficial owners or other persons entitled to vote those shares and the broker does not have discretionary voting authority to vote those shares on that particular matter. Broker non-votes and abstentions will have no effect on the outcome of any of the proposals. A proxy marked "WITHHOLD" will have the same effect as an abstention.

        The record date for the meeting will apply to any adjournment or postponement of the meeting unless our Board fixes a new record date for the adjourned or postponed meeting. If we adjourn the annual meeting, we will announce the time and place of the adjourned meeting at the original meeting, but we do not intend to deliver another notice of the meeting unless we fix a new record date for the adjourned meeting. At any subsequent reconvening of the annual meeting, all proxies will be voted in the same manner as they would have been at the original convening of the meeting (except for any proxies that have been effectively revoked or withdrawn).

        IMPORTANT: If your shares are held in the name of a brokerage firm, bank, nominee or other institution, you should provide instructions to your broker, bank, nominee or other institution on how to vote your shares. Please contact the person responsible for your account and give instructions for a proxy to be completed for your shares. If you have any questions or need assistance in voting your shares, please call the firm assisting us in the solicitation of proxies:

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, New York 10022
Brokers and Banks Call Collect at (212) 750-5833
Shareholders Call Toll-Free at (877) 717-3922

        A shareholder of record who has given a proxy may revoke it any time prior to its exercise by delivering to our Secretary at Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458, a written revocation, by delivering a duly executed proxy bearing a later date, by authorizing at a later date a proxy to vote his or her common shares over the internet or by telephone in the manner provided on the website indicated in the Notice of Internet Availability or by attending the meeting and voting his or her common shares in person. If a shareholder of record wants to receive a paper or email copy of the proxy card, he or she may request one from our Secretary at Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458. Proxies submitted by mail, over the internet or by telephone must be received by 11:59 p.m. Eastern Time on May 12, 2013. If your shares are held in the name of a brokerage firm, bank, nominee or other institution and you wish to change a prior instruction you gave to your brokerage firm, bank, nominee or other institution to vote your shares, you must follow the brokerage firm's, bank's, nominee's or other institution's instructions for changing your prior voting instructions. In addition, if you hold shares in the name of a brokerage

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firm, bank, nominee or other institution, you must provide a legal proxy from that institution in order to vote your shares at the meeting.

        Our principal executive offices are located at Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458.

        Our website address is included in this proxy statement as a textual reference only, and the information in the website is not incorporated by reference into this proxy statement.

Notice Regarding the Availability of Proxy Materials

        From the date of mailing of the Notice of Internet Availability through the conclusion of the meeting, shareholders will be able to access all of the proxy materials on the internet at www.proxyvote.com. The proxy materials will be available free of charge. The Notice of Internet Availability will instruct you as to how you may access and review all of the important information contained in the proxy materials (including our annual report to shareholders) over the internet or through other methods specified at the website designated in the Notice of Internet Availability. The website designated contains instructions as to how to vote over the internet or by telephone. The Notice of Internet Availability also instructs you as to how you may request a paper or email copy of the proxy card. If you received a Notice of Internet Availability and would like to receive printed copies of the proxy materials, you should follow the instructions for requesting such materials included in the Notice of Internet Availability.

PROPOSALS 1 AND 2
ELECTION OF TRUSTEES

        The number of our Trustees is fixed at five, and our Board is divided into three classes, with two Trustees in Class I, two Trustees in Class II and one Trustee in Class III. Trustees in each class are elected for three year terms and serve until their successors are elected and qualified.

        Our current Trustees are Jeffrey P. Somers and Barry M. Portnoy in Class I with a term of office expiring at the meeting to which this proxy statement relates, Donna D. Fraiche and Adam D. Portnoy in Class II with a term of office expiring at our 2014 annual meeting of shareholders and William A. Lamkin in Class III with a term of office expiring at our 2015 annual meeting of shareholders. The term of the Class I Trustees elected at the meeting to which this proxy statement relates will expire at our 2016 annual meeting of shareholders.

        Our Trustees are also categorized as Independent Trustees or Managing Trustees. Our Board is composed of three Independent Trustees and two Managing Trustees. Our Independent Trustees are not employees of Reit Management & Research LLC, or RMR, our manager, are not involved in our day to day activities and are persons who qualify as independent under the applicable rules of the NYSE and the Securities and Exchange Commission, or SEC. Our Managing Trustees are Trustees who have been employees, officers or directors of RMR or involved in our day to day activities for at least one year. Messrs. Lamkin and Somers and Ms. Fraiche are our Independent Trustees, and Messrs. Barry Portnoy and Adam Portnoy are our Managing Trustees. Biographical information relating to our Trustees and other information relating to our Board appears elsewhere in this proxy statement.

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PROPOSAL 1: ELECTION OF ONE INDEPENDENT TRUSTEE

        Our Board has nominated Mr. Jeffrey P. Somers for election as the Independent Trustee in Class I, whose nomination was recommended to our Board by our Nominating and Governance Committee. The term of the Independent Trustee in Class I elected at the meeting will expire at our 2016 annual meeting of shareholders. The persons named in the accompanying proxy intend to exercise properly executed and delivered proxies "FOR" the election of Mr. Somers, except to the extent that properly completed proxies indicate that the votes should not be so cast.

        Mr. Somers has agreed to serve as the Independent Trustee in Class I if elected. If, however, Mr. Somers becomes unable or unwilling to accept election to our Board, the proxies will be voted for the election of a substitute nominee designated by our Board. Our Board has no reason to believe that Mr. Somers will be unable or unwilling to serve.

        Mr. Somers will be elected as the Independent Trustee in Class I if he receives a plurality of all the votes cast.

        Our Board recommends you vote "FOR" the election of Mr. Somers as the Independent Trustee in Class I.

PROPOSAL 2: ELECTION OF ONE MANAGING TRUSTEE

        Our Board has nominated Mr. Barry M. Portnoy for election as the Managing Trustee in Class I, whose nomination was recommended to our Board by our Nominating and Governance Committee. The term of the Managing Trustee in Class I elected at the meeting will expire at our 2016 annual meeting of shareholders. The persons named in the accompanying proxy intend to exercise properly executed and delivered proxies "FOR" the election of Mr. Barry M. Portnoy, except to the extent that properly completed proxies indicate that the votes should not be so cast.

        Mr. Barry M. Portnoy has agreed to serve as the Managing Trustee in Class I if elected. If, however, Mr. Barry M. Portnoy becomes unable or unwilling to accept election to our Board, the proxies will be voted for the election of a substitute nominee designated by our Board. Our Board has no reason to believe that Mr. Barry M. Portnoy will be unable or unwilling to serve.

        Mr. Barry M. Portnoy will be elected as the Managing Trustee in Class I if he receives a plurality of all the votes cast.

        Our Board recommends you vote "FOR" the election of Mr. Barry M. Portnoy as the Managing Trustee in Class I.

PROPOSAL 3
RATIFICATION OF APPOINTMENT OF INDEPENDENT REGISTERED
PUBLIC ACCOUNTING FIRM

        On February 21, 2013, our Audit Committee voted to appoint Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2013 (our fiscal year being a calendar year). Ernst & Young LLP acted as our independent registered public accounting firm for 2012. A representative of Ernst & Young LLP is expected to be present at the meeting, with the opportunity to make a statement if he or she desires to do so. This representative will be available to respond to appropriate questions from shareholders who are present at the meeting. Proposal 3 is

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nonbinding. If the appointment is not ratified, our Audit Committee will consider whether to appoint another independent registered public accounting firm in its discretion. If the appointment is ratified, our Audit Committee, in its discretion, may appoint a different independent registered public accounting firm at any time if it determines that such a change would be advisable.

        The fees and expenses for services provided by Ernst & Young LLP to us for 2012 were as follows:

        Our Audit Committee has established policies and procedures that are intended to control the services provided by our independent registered public accounting firm and to monitor their continuing independence. Under these policies, no services may be undertaken by our independent registered public accounting firm unless the engagement is specifically approved by our Audit Committee or the services are included within a category that has been approved by our Audit Committee. The maximum charge for services is established by our Audit Committee when the specific engagement or the category of services is approved. In certain circumstances, our management is required to notify our Audit Committee when approved services are undertaken and the Audit Committee or its Chair may approve amendments or modifications to the engagement or the maximum fees. Our Director of Internal Audit is responsible to report to our Audit Committee regarding compliance with these policies and procedures.

        Our Audit Committee will not approve engagements of our independent registered public accounting firm to perform non-audit services for us if doing so will cause our independent registered public accounting firm to cease to be independent within the meaning of applicable SEC or NYSE rules. In other circumstances, our Audit Committee considers, among other things, whether our independent registered public accounting firm is able to provide the required services in a more or less effective and efficient manner than other available service providers and whether the services are consistent with the Public Company Accounting Oversight Board Rules.

        All services for which we engaged our independent registered public accounting firm in 2012 were approved by our Audit Committee. The total fees for audit and non-audit services provided by Ernst & Young LLP in 2012 are set forth above. The tax fees charged by Ernst & Young LLP during 2012 were for tax compliance services related to our 1099 calculations for the fiscal year ended December 31, 2012. Our Audit Committee approved the engagement of Ernst & Young LLP to provide these non-audit services because it determined that Ernst & Young LLP providing these services would not compromise its independence and that its familiarity with our record keeping and accounting systems would permit it to provide these services with equal or higher quality, more quickly and at a lower cost than we could obtain these services from other providers.

        The affirmative vote of a majority of the votes cast will be necessary for the ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm for the fiscal

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year ending December 31, 2013. The shareholder vote on proposal 3 is advisory and nonbinding and serves only as a recommendation to our Board.

        Our Board recommends you vote "FOR" the ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2013.

SOLICITATION OF PROXIES

        Proxies may be solicited, without additional compensation, by our Trustees and officers, and by RMR and its directors, officers and employees, by mail, telephone or other electronic means or in person. We are paying the costs of this solicitation, including the preparation, printing, mailing and website hosting of proxy materials. We will request banks, brokers and other custodians, nominees and fiduciaries to forward proxy materials to the beneficial owners of our common shares and to obtain their voting instructions. We will reimburse those firms for their expenses. In addition, we have retained Innisfree to assist in the solicitation of proxies for a fee of $15,000 plus reimbursement of expenses. We have agreed to indemnify Innisfree against certain liabilities arising out of our agreement with Innisfree.

TRUSTEES AND EXECUTIVE OFFICERS

        The following are the ages and recent principal occupations, as of February 24, 2013, of our nominees, Trustees and executive officers. Unless otherwise specified, the business address of our nominees, Trustees and executive officers is c/o Select Income REIT, Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458.

Independent Trustee Nominee for a Term Expiring in 2016

JEFFREY P. SOMERS, Age: 69

        Mr. Somers has been one of our Independent Trustees since shortly before the completion of our initial public offering in 2012. Mr. Somers has been, since 2010, Of Counsel to, and from 1995 to 2009, was a member, and for six of those years the managing member, of the law firm of Morse, Barnes-Brown & Pendleton, PC. Prior to that time, he was a partner for more than 20 years at the law firm of Gadsby Hannah LLP (now McCarter & English, LLP) and for eight of those years was managing partner of the firm. Since 2002, Mr. Somers has served as a Director for Cantella Management Corp., a holding company for Cantella & Co., Inc., an SEC registered broker dealer. From 1995 to 2001, he served as a trustee for the Pictet Funds. Before entering private law practice, Mr. Somers was a staff attorney at the SEC in Washington, D.C. He has previously served as a trustee for Glover Hospital, which is now part of Beth Israel Deaconess Hospital, among various other civic leadership roles. Mr. Somers has been an Independent Trustee of RMR Real Estate Income Fund, or RIF, and its predecessor funds since 2009 and was an Independent Trustee of RMR Funds Series Trust from 2009 until its dissolution in 2009.⁽¹⁾ Mr. Somers has been an Independent Trustee of Senior Housing Properties Trust, or SNH, and Government Properties Income Trust, or GOV, since 2009.

   

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(1)

RIF, its predecessor funds and RMR Funds Series Trust are collectively referred to herein as the "RMR Funds."

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        Our Board concluded that Mr. Somers is qualified to serve as one of our Independent Trustees based upon, among other things, his expertise in legal, corporate governance and regulatory matters, his leadership role as a law firm managing member, his service as a trustee of public investment companies, his experience in complex business transactions, his various civic roles, his familiarity with finance and accounting matters and his qualifying as an Independent Trustee in accordance with the requirements of the NYSE, the SEC, our declaration of trust and our bylaws. Mr. Somers is an Independent Trustee in Class I and, if elected at the meeting, his term will expire at our 2016 annual meeting of shareholders.

Managing Trustee Nominee for a Term Expiring in 2016

BARRY M. PORTNOY, Age: 67

        Mr. Barry M. Portnoy has been one of our Managing Trustees since our formation in 2011. Mr. Portnoy has been a Managing Trustee of CommonWealth REIT, or CWH, Hospitality Properties Trust, or HPT, SNH and GOV, since 1986, 1995, 1999 and 2009, respectively. He has been a Managing Director of Five Star Quality Care, Inc., or Five Star, and of TravelCenters of America LLC, or TA, since 2001 and 2006, respectively. Mr. Portnoy is an owner of RMR and of RMR Advisors, Inc., or RMR Advisors, an SEC registered investment advisor. Mr. Portnoy has been an owner and a Director of RMR (and its predecessor) since its founding in 1986, a full time employee of RMR since 1997, the Chairman of RMR since 1998 and a Director and Vice President of RMR Advisors since 2002. Mr. Portnoy has been an Interested Trustee of the RMR Funds since shortly after their formation (the earliest of which was in 2002). Mr. Portnoy practiced law for many years as a partner in, and chairman of, a law firm until 1997. Mr. Barry Portnoy is the father of Mr. Adam Portnoy, our other Managing Trustee.

        Our Board concluded that Mr. Portnoy is qualified to serve as one of our Managing Trustees based upon, among other things, his demonstrated leadership capability, his extensive experience in and knowledge of the commercial real estate industry and real estate investment trusts, or REITs, his leadership position with RMR, his extensive public company director service, his professional skills and expertise in, among other things, legal and regulatory matters and his institutional knowledge earned through prior service on CWH's board of trustees and in key leadership positions with our manager and his qualifying as a Managing Trustee in accordance with the requirements of our declaration of trust and our bylaws. Mr. Barry Portnoy is a Managing Trustee in Class I and, if elected at the meeting, his term will expire at our 2016 annual meeting of shareholders.

Independent Trustees Continuing in Office

DONNA D. FRAICHE, Age: 61

        Ms. Fraiche has been one of our Independent Trustees since shortly before the completion of our initial public offering in 2012. Ms. Fraiche is a shareholder in, and serves on the nominating and governance committee of, Baker, Donelson, Bearman, Caldwell & Berkowitz, PC and has practiced law in the Health Law and Public Policy Departments of that firm since 2004. Previously, Ms. Fraiche practiced law with the firm now known as Locke Lord LLP in New Orleans. Ms. Fraiche is Chair of the Louisiana Health Care Commission and has previously served as President of the organization now known as the American Health Lawyers Association, Chair of the Long Term Community Planning Task Force and Health Care Committee of the Louisiana Recovery Authority, delegate of the Louisiana

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Recovery Authority to the Louisiana Health Care Redesign Collaborative, Chair of the Louisiana Office of State Planning Task Force and Chair of the Board of Trustees of Loyola University, among numerous other business and civic responsibilities. Ms. Fraiche has testified before Congressional and Senate committees on the structure of the hospital industry and the Gulf Coast's reconstruction efforts after hurricanes Katrina and Rita. Ms. Fraiche has also served on the adjunct faculty of Tulane University's School of Public Health and Administration and as a preceptor for its residency program in health management systems and has been widely published on the topics of health care and the Gulf Coast's reconstruction efforts. Ms. Fraiche also serves as Honorary Consul General for Japan in New Orleans. Ms. Fraiche has been an Independent Director of Five Star since 2010.

        Our Board concluded that Ms. Fraiche is qualified to serve as one of our Independent Trustees based upon, among other things, her professional legal skills, her many leadership roles and experiences, including her service in numerous public policy and civic leadership roles and her qualifying as an Independent Trustee in accordance with the requirements of the NYSE, the SEC, our declaration of trust and our bylaws. Ms. Fraiche is an Independent Trustee in Class II, and her term expires at our 2014 annual meeting of shareholders.

WILLIAM A. LAMKIN, Age: 53

        Mr. Lamkin has been one of our Independent Trustees since shortly before the completion of our initial public offering in 2012. Mr. Lamkin has been a partner in Ackrell Capital LLC, a San Francisco based investment bank, since 2003. Previously, he was employed as a financial consultant and as an investment banker, including as a Senior Vice President in the investment banking division of ABN AMRO, Incorporated. Prior to working as a financial consultant and as an investment banker, Mr. Lamkin was a practicing attorney. Mr. Lamkin has served as an Independent Trustee of CWH and HPT since 2006 and 2007, respectively.

        Our Board concluded that Mr. Lamkin is qualified to serve as one of our Independent Trustees based upon, among other things, his experience in and knowledge of the commercial real estate and investment banking industries, his work on and with public company boards and board committees, his demonstrated management ability, his experience in capital raising and strategic business transactions, his professional training, skills and expertise in, among other things, legal and finance matters, his institutional knowledge earned through service on CWH's board of trustees for seven years and his qualifying as an Independent Trustee in accordance with the requirements of the NYSE, the SEC, our declaration of trust and our bylaws. Mr. Lamkin is an Independent Trustee in Class III, and his term expires at our 2015 annual meeting of shareholders.

Managing Trustee Continuing in Office

ADAM D. PORNTOY, Age: 42

        Mr. Adam D. Portnoy has been one of our Managing Trustees since our formation in 2011. Mr. Portnoy has been a Managing Trustee of CWH since 2006 and its President since 2011. He also served as Executive Vice President of CWH from 2003 through 2006. Mr. Portnoy has been a Managing Trustee of HPT, SNH and GOV, since 2007, 2007 and 2009, respectively. Mr. Portnoy has been an Interested Trustee of RIF and its predecessor funds since 2009. Mr. Portnoy has been President of CWH since 2011 and was an Executive Vice President of CWH from 2003 through 2006. He was President of GOV from 2009 until 2011. Mr. Portnoy has been an executive officer of RMR

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since 2003 and currently is the President, Chief Executive Officer and a Director of RMR. Additionally, Mr. Portnoy is an owner of RMR and of RMR Advisors. Mr. Portnoy has been President and Director of RMR Advisors since 2007 and was a Vice President prior to that time since 2003. He has also been President of the RMR Funds since 2007. Prior to becoming President in 2007, Mr. Portnoy served as Vice President of the RMR Funds beginning in 2004. Prior to 2004, Mr. Portnoy held various positions in the finance industry and public sector, including working as an investment banker at Donaldson, Lufkin & Jenrette and ABN AMRO, working in private equity at the International Finance Corporation (a member of The World Bank Group) and DLJ Merchant Banking Partners, and serving as Chief Executive Officer of a telecommunications company. Mr. Portnoy is also currently a member of the Board of Governors of the National Association of Real Estate Trusts, a member of the Board of Trustees of Occidental College and serving as the Honorary Consul General of the Republic of Bulgaria to Massachusetts. Mr. Adam Portnoy is the son of Mr. Barry Portnoy, our other Managing Trustee.

        Our Board concluded that Mr. Portnoy is qualified to serve as one of our Managing Trustees based upon, among other things, his extensive experience in and knowledge of the commercial real estate industry and REITs, his leadership position with RMR, his public company director service, his demonstrated management ability, his experience in investment banking and private equity, his government organization service, his institutional knowledge earned through service on CWH's board of trustees for seven years and in key leadership positions with our manager for nine years and his qualifying as a Managing Trustee in accordance with the requirements of our declaration of trust and our bylaws. Mr. Portnoy is a Managing Trustee in Class II, and his term expires at our 2014 annual meeting of shareholders.

Executive Officers

DAVID M. BLACKMAN, Age: 50

        Mr. Blackman has been our President and Chief Operating Officer since our formation in 2011. Mr. Blackman has also been President and Chief Operating Officer of GOV since 2011 and was Treasurer and Chief Financial Officer of GOV from 2009 until 2011. Previously, Mr. Blackman had been employed as a banker at Wachovia Corporation and its predecessors for 23 years, focused on real estate finance matters, including serving as a Managing Director in the real estate section of Wachovia Capital Markets, LLC from 2005 through 2009. Mr. Blackman has also been employed as a Senior Vice President of RMR since 2009.

JOHN C. POPEO, Age: 52

        Mr. Popeo has been our Treasurer and Chief Financial Officer since our formation in 2011. Mr. Popeo has also been Treasurer and Chief Financial Officer of CWH since 1999 and Assistant Secretary of CWH since 2008, and served as Secretary of CWH from 1999 to 2008. Mr. Popeo has also been an Executive Vice President of RMR since 2008, and previously served as Treasurer of RMR from 1997 to 2012, as a Vice President from 1999 to 2006 and as a Senior Vice President from 2006 to 2008. Mr. Popeo served as Vice President of RMR Advisors from 2004 to 2009 and served as Vice President of the RMR Funds from shortly after their formation (the earliest of which was in 2002) until 2009. Mr. Popeo is a certified public accountant.

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        Except as noted with regard to Mr. Barry Portnoy and Mr. Adam Portnoy, there are no family relationships among any of our Trustees or executive officers. Our executive officers serve at the discretion of our Board.

        RMR, RMR Advisors, CWH, GOV, HPT, SNH, Five Star, TA and the RMR Funds may be considered to be affiliates of us. RMR is a privately owned company that provides management services to public and private companies, including us, CWH, GOV, HPT, SNH, Five Star and TA. CWH is a publicly traded REIT that primarily owns office buildings. GOV is a publicly traded REIT that primarily invests in properties that are majority leased to government tenants. HPT is a publicly traded REIT that primarily owns hotels and travel centers. SNH is a publicly traded REIT that primarily owns senior living properties and medical office buildings. Five Star is a publicly traded real estate based operating company in the healthcare and senior living services business. TA is a publicly traded real estate based operating company in the travel center business. The RMR Funds are or were investment companies registered under the Investment Company Act of 1940, as amended. RMR Advisors is an SEC registered investment adviser to the RMR Funds.

BOARD OF TRUSTEES

        Our business is conducted under the general direction of our Board as provided by our declaration of trust, our bylaws and the laws of the State of Maryland, the state in which we were organized on December 19, 2011.

        Three of our Trustees, Donna D. Fraiche, William A. Lamkin and Jeffrey P. Somers, are our Independent Trustees within the meaning of our bylaws. Two of our Trustees, Adam D. Portnoy and Barry M. Portnoy, are our Managing Trustees within the meaning of our bylaws.

        Our bylaws require that a majority of our Board be Independent Trustees. In determining the status of those Trustees who qualify as Independent Trustees, each year our Board affirmatively determines whether Trustees have a direct or indirect material relationship with us, including our subsidiaries, other than serving as our Trustees. When assessing a Trustee's relationship with us, our Board considers all relevant facts and circumstances, not merely from the Trustee's standpoint, but also from that of the persons or organizations with which the Trustee has an affiliation.

        Our Board has determined that Messrs. Lamkin and Somers and Ms. Fraiche currently qualify as independent trustees under applicable NYSE rules and are Independent Trustees under our bylaws. In making these determinations, our Board considered each of these three Trustees' service in other enterprises and on the boards of other companies to which RMR and its affiliates provide management services. Our Board has concluded that none of these three Trustees possessed or currently possesses any relationship that could impair his or her judgment in connection with his or her duties and responsibilities as a Trustee or that could otherwise be a direct or indirect material relationship under applicable NYSE standards.

        During 2012, our Board held six meetings, our Audit Committee held seven meetings, our Compensation Committee held four meetings and our Nominating and Governance Committee held two meetings. In addition, certain of our Trustees met four times as a special committee during 2012 to consider various matters. During 2012, each Trustee attended 75% or more of the total number of meetings of our Board and any committee of which he or she was a member during the time in which he or she served on our Board or such committee. As we became a public company in 2012, we did not hold an annual meeting of shareholders as a public company in 2012.

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        Pursuant to our Governance Guidelines, our Independent Trustees meet at least once each year without management. The presiding Trustee at these meetings is the Chair of our Audit Committee, unless the Independent Trustees in attendance select another Independent Trustee to preside.

        We do not maintain directors' and officers' liability insurance for our Trustees and officers. Subject to certain limitations, our declaration of trust, our bylaws and separate indemnification agreements that we have entered into require that we indemnify our Trustees and officers.

Board Leadership Structure

        Our Board is comprised of both Independent Trustees and Managing Trustees, with a majority being Independent Trustees. Our Independent Trustees are not employees of RMR, are not involved in our day to day activities and are persons who qualify as independent under the applicable rules of the NYSE and SEC. Our Managing Trustees have been employees, officers or directors of RMR or involved in our day to day activities for at least one year. Our Board is composed of three Independent Trustees and two Managing Trustees. Our President and our Treasurer are not members of our Board, but they regularly attend Board meetings, as does our Director of Internal Audit. Other officers of RMR also sometimes attend Board meetings at the invitation of our Board.

        Our Audit, Compensation and Nominating and Governance Committees are comprised solely of our Independent Trustees, and an Independent Trustee serves as Chair of each such committee. These standing committees have responsibilities related to our leadership and governance, including among other things: (1) our Audit Committee reviews our financial reports, oversees our accounting and financial reporting processes, selects our independent accountants, determines the fees paid to our independent accountants and assists our Board with its oversight of our internal audit function, our risk management and our compliance with legal and regulatory requirements; (2) our Compensation Committee annually evaluates the performance of our Director of Internal Audit and approves the compensation we pay to him, determines any compensation that we directly pay to our President, reviews and approves any compensation that we directly pay to our Treasurer and any other senior executive of ours who is also a senior executive of RMR, reviews our business and property management agreements with RMR, evaluates RMR's performance under those agreements, approves the fees and certain other costs that we pay under those agreements, determines whether those agreements will be renewed, amended, terminated or allowed to expire and administers all of our equity compensation awards; and (3) our Nominating and Governance Committee considers nominees to serve on our Board, recommends to our Board nominees for election to our Board, assesses our Board's performance and reviews and assesses our Board leadership structure and Governance Guidelines and recommends to the Board any changes it determines appropriate. The Chairs of our Audit, Compensation and Nominating and Governance Committees set the agenda for their respective committee meetings, but committee members, our Managing Trustees or members of our management may suggest agenda items to be considered by these committees.

        We do not have a Chairman of our Board or a lead Independent Trustee. Our President, any Managing Trustee or any two Independent Trustees may call a special meeting. Our Managing Trustees, in consultation with our President and Treasurer, set the agenda for our Board meetings, and any Independent Trustee may place an item on an agenda by providing notice to a Managing Trustee, our President or our Treasurer. Discussions at Board meetings are led by the Managing Trustee or Independent Trustee who is most knowledgeable on a subject. Our Board is small, which facilitates informal discussions and communication from management to the Board and among Trustees. Our

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Independent Trustees meet to consider Company business without the attendance of our Managing Trustees or our officers, and they meet separately with our officers, with our Director of Internal Audit and with our outside accountants. In such meetings of our Independent Trustees, the Chair of the Audit Committee presides unless the Independent Trustees determine otherwise.

        In light of the size of our Board and the oversight provided by and involvement of our Independent Trustees and Board committees in the leadership of our Company, our Board considers that our current leadership structure and conduct combines appropriate leadership with the ability to conduct our business efficiently and with appropriate care and attention.

Risk Oversight

        Our Board oversees risk as part of its general oversight of our Company, and oversight of risk is addressed as part of various Board and Board committee activities and through regular and special Board and Board committee meetings. The actual day to day business of our Company is conducted by RMR, and RMR implements risk management in its activities. In discharging their oversight responsibilities, our Board and Board committees regularly review a wide range of reports provided to them by RMR and other service providers, including reports on market and industry conditions, operating and compliance reports, financial reports, reports on risk management activities, regulatory and legislative updates that may impact us, legal proceedings updates and reports on other business related matters, and discusses such matters among themselves and with representatives of RMR, counsel and our independent accountants. Our Audit Committee, which meets at least quarterly and reports its findings to our Board, performs a lead role in helping our Board fulfill its responsibilities for oversight of our financial reporting, internal audit function, risk management and our compliance with legal and regulatory requirements. Our Board and Audit Committee review periodic reports from our independent registered public accounting firm regarding potential risks, including risks related to our internal controls. Our Audit Committee also annually reviews, approves and oversees an internal audit plan developed by our Director of Internal Audit with the goal of helping our Company systematically evaluate the effectiveness of our risk management, control and governance processes, and periodically meets with our Director of Internal Audit to review the results of our internal audits, and directs or recommends to the Board actions or changes it determines appropriate to enhance or improve the effectiveness of our risk management. Our Compensation Committee also evaluates the performance of our Director of Internal Audit and RMR's performance under our business and property management agreements. Also, our Compensation Committee and our Board consider the fact that we have a share grant program that requires share grants to vest over a period of years, rather than a stock option program such as is employed by many other publicly owned companies. We believe that the use of share grants vesting over time rather than stock options mitigates the incentives for our management to undertake undue risks and encourages our management to make longer term, less risk prone decisions.

        While a number of risk management functions are performed, it is not possible to identify all of the risks that may affect us or to develop processes and controls to eliminate all risks and their possible effects, and processes and controls employed to address risks may be limited in their effectiveness. Moreover, it is necessary for our Company to bear certain risks to achieve our objectives. As a result of the foregoing and other factors, our Company's ability to manage risk is subject to substantial limitations.

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BOARD COMMITTEES

        We have a standing Audit Committee, Compensation Committee and Nominating and Governance Committee, each of which has a written charter. Each of the above committees is currently comprised of Messrs. Lamkin and Somers and Ms. Fraiche, who are independent under applicable NYSE listing standards and each committee's respective charter, and, in the case of our Audit Committee, the applicable independence requirements of the SEC. Our Audit Committee, Compensation Committee and Nominating and Governance Committee are delegated the powers of our Board necessary to carry out their responsibilities.

        Our Audit Committee was established in accordance with Section 3(a)(58)(A) of the Exchange Act. The primary function of our Audit Committee is to select our independent registered public accounting firm and to assist our Board in fulfilling its responsibilities for oversight of: (1) the integrity of our financial statements; (2) our compliance with legal and regulatory requirements; (3) our independent registered public accounting firm's qualifications and independence; and (4) the performance of our internal audit function and independent registered public accounting firm. Our Board has determined that Mr. Lamkin is our audit committee financial expert and is "independent" as defined by the rules of the SEC and the NYSE. Our Board's determination that Mr. Lamkin is a financial expert was based upon: (1) his current position as partner of Ackrell Capital LLC, an investment banking firm; and (2) his prior experience (a) as a financial consultant, (b) as a Senior Vice President in the investment banking division of ABN AMRO, Incorporated, (c) in various investment banking positions with Donaldson, Lufkin & Jenrette, PaineWebber and Kidder, Peabody, where his work included real estate investment banking and project financing matters and (d) as a member and chair of the audit committees of other publicly owned REITs. Additionally, our Board has determined that Mr. Somers's simultaneous service on the audit committees of SNH, GOV and RIF will not impair his ability to effectively serve on our Audit Committee. Under its charter, our Audit Committee has the final authority and responsibility to select our independent registered public accounting firm.

        Our Compensation Committee's primary responsibilities include: (1) reviewing the terms of RMR's business management and property management agreements with us, evaluating the performance of RMR under those agreements, approving the fees and certain other costs that we are required to pay under those agreements and making determinations regarding continuance of or changes to those agreements; (2) evaluating the performance of our President and determining and approving any compensation, including any equity compensation, paid directly by us to our President; (3) evaluating the performance of our Director of Internal Audit and determining the compensation payable to him and the costs of our internal audit function generally; (4) evaluating, approving and administering all of our equity compensation plans; (5) evaluating whether our executive compensation programs encourage appropriate levels of risk taking by our executives; and (6) reviewing and considering the incentives and risks associated with our compensation policies and practices.

        The responsibilities of our Nominating and Governance Committee include: (1) identification of individuals qualified to become members of our Board and recommending to our Board the nominees for Trustee for each annual meeting of shareholders or when Board vacancies occur; (2) development and recommendation to our Board of governance guidelines; and (3) evaluation of the performance of our Board.

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        The charter of each of our standing committees provides that the committee may form and delegate authority to subcommittees of one or more members when appropriate. Subcommittees are subject to the provisions of the applicable committee's charter.

        Our policy with respect to Board members' attendance at our annual meetings of shareholders can be found in our Governance Guidelines, the full text of which appears at our website at www.sirreit.com. In addition to our Governance Guidelines, copies of the charters of our Audit, Compensation and Nominating and Governance Committees, as well as our Code of Business Conduct and Ethics, may be obtained free of charge at our website, www.sirreit.com, or by writing to our Secretary, Select Income REIT, Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458.

COMMUNICATIONS WITH TRUSTEES

        Any shareholder or other interested person who desires to communicate with our Independent Trustees or any Trustees, individually or as a group, may do so by filling out a report at our website, www.sirreit.com, by calling our toll-free confidential message system at (866) 511-5038 or by writing to the party for whom the communication is intended, c/o Director of Internal Audit, Select Income REIT, Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458. Our Director of Internal Audit will then deliver any communication to the appropriate party or parties.

SELECTION OF CANDIDATES FOR TRUSTEES;
SHAREHOLDER RECOMMENDATIONS, NOMINATIONS AND OTHER PROPOSALS

        Our Board has established Governance Guidelines which, together with our declaration of trust and our bylaws, set forth the qualifications for service on our Board. Our Governance Guidelines may be changed from time to time by our Board upon the recommendation of our Nominating and Governance Committee. Our Board makes nominations of persons to be elected by shareholders as Trustees. Our Board also elects Trustees to fill Board vacancies that may occur from time to time. In both of these circumstances, our Board will act upon recommendations made by our Nominating and Governance Committee.

        In considering candidates to serve as Trustees, our Nominating and Governance Committee seeks individuals who have qualities that the Committee believes will be effective in serving our long term best interests. Among the characteristics that the Committee considers are the following: integrity, experience, achievements, judgment, intelligence, competence, personal character, ability to make independent analytical inquiries, willingness to devote adequate time to Board duties, likelihood that a candidate will be able to serve on our Board for an extended period and other matters that our Nominating and Governance Committee deems appropriate. While our Board does not have a specific diversity policy in connection with the selection of nominees for Trustee, due consideration is given to our Board's desire for an overall balance of diversity of perspectives, backgrounds and experiences. Our Board does not consider gender, sexual orientation, race, religion, ethnicity, national origin or citizenship to be relevant considerations and does not discriminate on the basis of such criteria. When considering candidates, our Nominating and Governance Committee will also assist our Board in determining the desired mix of experience, skills, attributes and other criteria that will strengthen our Board in a way that best serves the long term interests of our Company and complement the experience, skills, attributes and qualifications of existing Trustees. Depending on whether the position to be filled is that of an Independent Trustee or a Managing Trustee, the qualifications of the candidate

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to meet the criteria for each such category of Trustee is considered. In seeking candidates for Trustee who have not previously served as one of our Trustees, the Nominating and Governance Committee may use the business, professional and personal contacts of its members, it may accept recommendations from other Board members and, if it considers it appropriate, the Nominating and Governance Committee may engage a professional search firm.

        In 2012, we did not pay any third party to identify or to assist in the evaluation of any candidate for election to our Board. We did not receive any shareholder recommendations or nominations for our Board for the 2013 annual meeting of shareholders, except the nominations made by our Board and recommendations by our Nominating and Governance Committee, each of which includes Board members who are shareholders of record.

        Shareholder Recommendations for Nominees.    A responsibility of our Nominating and Governance Committee is to consider candidates for election as Trustee who are properly recommended by shareholders. To be considered by our Nominating and Governance Committee, a shareholder recommendation for a nominee must be made by such shareholder's written notice to the Chair of our Nominating and Governance Committee and our Secretary, which notice should contain or be accompanied by the information and documents with respect to the recommended nominee and recommending shareholder that the recommending shareholder believes to be relevant or helpful to our Nominating and Governance Committee's deliberations. Our Nominating and Governance Committee may request additional information about the shareholder recommended nominee or about the shareholder recommending the nominee. Any recommended nominee will be considered by our Nominating and Governance Committee in its discretion using the same criteria as other candidates considered by it.

        The preceding paragraph applies only to shareholder recommendations for nominees to our Nominating and Governance Committee. A shareholder nomination must be made in accordance with the provisions of our bylaws, including the procedures discussed below, and applicable state and federal laws.

        2014 Annual Meeting Deadlines for Shareholder Proposals Pursuant to Rule 14a-8 under the Exchange Act.    Shareholder proposals intended to be presented pursuant to Rule 14a-8 under the Exchange Act at our 2014 annual meeting of shareholders must be received at our principal executive offices on or before October 28, 2013, in order to be considered for inclusion in our proxy statement for our 2014 annual meeting of shareholders, provided that if we hold our 2014 annual meeting on a date that is more than 30 days before or after May 13, 2014, shareholders must submit proposals for inclusion in our 2014 proxy statement within a reasonable time before we begin to print our proxy materials. Under Rule 14a-8, we are not required to include shareholder proposals in our proxy materials unless conditions specified in the rule are met.

        2014 Annual Meeting Deadlines for Shareholder Nominations and Shareholder Proposals Not Made Pursuant to Rule 14a-8 under the Exchange Act.    In order for a shareholder properly to propose a nominee for election to our Board or propose business outside of Rule 14a-8 under the Exchange Act, the shareholder must comply in all respects with the advance notice and other provisions set forth in our bylaws, which currently include, among other things, requirements as to the shareholder's timely delivery of advance notice, ownership of at least a specified minimum amount of our common shares for a specified minimum period of time, record ownership and submission of specified information. The notice must set forth detailed specified information about any proposed nominee, the shareholder

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making the nomination and affiliates and associates of that shareholder. As to any other business that the shareholder proposes to bring before the meeting, our bylaws provide that the notice must set forth a description of such business, the reasons for proposing such business at the meeting and any material interest in such business of the shareholder, a description of all agreements, arrangements and understandings involving the shareholder in connection with the proposal of such business and a representation that the shareholder intends to appear in person or by proxy at the meeting to bring the business before the meeting.

        In addition, at the same time as the submission of a shareholder nomination or proposal for consideration at a meeting of our shareholders that, if elected or approved and implemented by us, would cause us to be in breach of any covenant in or in default under any debt instrument or agreement or other material agreement of ours or any subsidiary of ours, our bylaws provide that the shareholder must submit to our Secretary (i) evidence satisfactory to our Board of the lender's or contracting party's willingness to waive the breach of covenant or default, or (ii) a detailed plan for repayment of the applicable indebtedness or curing the contractual breach or default and satisfying any resulting damage, specifically identifying the actions to be taken or the source of funds, which plan must be satisfactory to our Board in its discretion, and evidence of the availability to us of substitute credit or contractual arrangements similar to the credit or contractual arrangements which are implicated by the shareholder nomination or other proposal that are at least as favorable to us, as determined by our Board in its discretion.

        Our bylaws require that shareholder nominations and proposals intended to be made outside of Rule 14a-8 under the Exchange Act at our 2014 annual meeting of shareholders must be submitted, in accordance with the requirements of our bylaws to our Secretary at Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458, not later than 5:00 p.m. Eastern Time on October 28, 2013 (which is also the date, after which, shareholder nominations and proposals made outside of Rule 14a-8 under the Exchange Act would be considered "untimely" within the meaning of Rule 14a-4(c) under the Exchange Act) and not earlier than September 28, 2013; provided, that, if our 2014 annual meeting is called for a date that is more than 30 days earlier or later than May 13, 2014, then a shareholder's notice must be so delivered not later than 5:00 p.m. Eastern Time on the tenth day following the earlier of the day on which (1) notice of the date of our 2014 annual meeting is mailed or otherwise made available or (2) public announcement of the date of our 2014 annual meeting is first made by us. Neither the postponement or adjournment of an annual meeting, nor the public announcement of such postponement or adjournment, commences a new time period for the giving of a shareholder's notice as described above.

        The foregoing description of the procedures for a shareholder to propose a nomination for election to our Board or other business for consideration at an annual meeting is only a summary and is not a complete listing of all requirements. Copies of our bylaws, including the provisions that concern shareholder recommendations and the requirements for shareholder nominations and other proposals, may be obtained by writing to our Secretary at Select Income REIT, Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458, or from the SEC's website at www.sec.gov. Any shareholder considering making a nomination or other proposal should carefully review and comply with those provisions. Under our declaration of trust and our bylaws, a shareholder is obligated to indemnify us for costs and expenses we incur arising from the shareholder's breach or failure to fully comply with any covenant, condition or provision of our declaration of trust or our bylaws, including

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costs and expenses we may incur as a result of the shareholder's failure to comply with the requirements to make nominations and proposals.

COMPENSATION TABLES

        The following tables provide: (1) summary 2012 compensation information relating to our named executive officers; (2) information with respect to share awards made to, or held by, our named executive officers during the periods or at the dates specified below; and (3) compensation information relating to our Trustees for 2012. Our named executive officers consist of two individuals, our President and Chief Operating Officer and our Treasurer and Chief Financial Officer, the compensation of whom is required to be reported in this proxy statement under the rules of the SEC. None of our named executive officers are employed by us. Our manager, RMR, provides services that otherwise would be provided by employees and compensates our named executive officers directly and in RMR's sole discretion in connection with their services rendered to RMR and to us. We do not pay our executive officers salaries or bonuses or provide other compensatory benefits except for the grants of shares under our Share Award Plan.

SUMMARY COMPENSATION TABLE FOR 2012

        Share awards granted by us to our executive officers in 2012 provide that one fifth of each award vests on the grant date and one fifth vests on each of the next four anniversaries of the grant date. In the event a recipient granted a share award ceases to perform duties for us or ceases to be an officer or an employee of RMR or any company that RMR manages during the vesting period, at our option, the recipient shall forfeit or we may repurchase the common shares that have not yet vested for nominal consideration. Holders of vested and unvested shares awarded under our Share Award Plan are eligible to receive distributions that we make on our shares on the same terms as other holders of our common shares.

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OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END FOR 2012
(Shares granted in 2012, which have not yet vested)

POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

        From time to time, we have entered into arrangements with former employees of RMR in connection with the termination of their employment with RMR, providing for the acceleration of vesting of restricted shares previously granted to them under our Share Award Plan. Although we have no formal policy, plan or arrangement for payments to employees of RMR in connection with their termination of employment with RMR, we may in the future provide on a discretionary basis for similar payments depending on various factors we then consider relevant and if we believe it is in the Company's best interests to do so.

TRUSTEE COMPENSATION FOR 2012
(2012 compensation; all share grants to Trustees vest at the time of grant)

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        Each Independent Trustee receives an annual fee of $35,000 for services as a Trustee, plus a fee of $750 for each meeting attended. Up to two $750 fees are paid if a Board meeting and one or more Board committee meetings are held on the same date. The chairpersons of our Audit Committee, Compensation Committee and Nominating and Governance Committee receive an additional $10,000, $5,000 and $5,000, respectively, each year. Under our Governance Guidelines, each Trustee is required to maintain the necessary level of expertise to perform his or her responsibilities as Trustee and we reimburse each Trustee for the out of pocket costs he or she incurs from attending continuing education programs. In addition, each Trustee received a grant of 2,000 of our common shares in 2012. We generally reimburse all our Trustees for travel expenses incurred in connection with their duties as Trustees.

        Our Board believes it is important to align the interests of Trustees with those of our shareholders and for Trustees to hold equity ownership positions in our Company. Accordingly, our Board believes that a portion of each Trustee's compensation should be paid in shares. In determining the amount and composition of such compensation, our Board considers the compensation of trustees and directors of other comparable enterprises, both with respect to size and industry, including the compensation of trustees and directors of other companies managed by RMR.

        In 2012 our Board reviewed the compensation paid to our Trustees and determined both the amount of such compensation and the allocation of such compensation between equity based awards and cash. Our Managing Trustees do not receive any cash compensation for their services as Trustees, but they do receive common share grants equal to the share grants awarded to our Independent Trustees.

AUDIT COMMITTEE REPORT

        In the course of our oversight of the Company's financial reporting process, we have: (1) reviewed and discussed with management the audited financial statements for the year ended December 31, 2012; (2) discussed with Ernst & Young LLP, the Company's independent registered public accounting firm, the matters required to be discussed by the Statement on Auditing Standards No. 61, as amended (AICPA, Professional Standards, Vol. 1, AU section 380), as adopted by the Public Company Accounting Oversight Board in Rule 3200T; (3) received the written disclosures and the letter from the independent registered public accounting firm required by applicable requirements of the Public Company Accounting Oversight Board regarding the independent accountant's communications with the audit committee concerning independence; (4) discussed with the independent registered public accounting firm its independence; and (5) considered whether the provision of non-audit services by the independent registered public accounting firm is compatible with maintaining its independence and concluded that it is compatible at this time.

        Based on the foregoing review and discussions, the Audit Committee recommended to the Board that the audited financial statements be included in the Company's Annual Report on Form 10-K for the year ended December 31, 2012, for filing with the SEC.

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

        Unless otherwise indicated, the information set forth below is as of February 19, 2013. The following table sets forth information regarding the beneficial ownership of our common shares (excluding any fractional shares that may be beneficially owned by such persons) by: (1) each person or entity known to us to be the beneficial owner of more than 5% of our outstanding common shares; (2) each of our Trustees, nominees and the persons listed in the Compensation Tables in this proxy statement; and (3) our Trustees and executive officers as a group. Unless otherwise indicated, we believe that each owner named below has sole voting and investment power for all our common shares shown to be beneficially owned by that person or entity. As of the date first set forth in this paragraph, we do not know of any outstanding rights to acquire our shares of the type specified in Rule 13d-3(d)(1) under the Exchange Act.

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RELATED PERSON TRANSACTIONS AND COMPANY REVIEW OF SUCH TRANSACTIONS

        We have adopted written Governance Guidelines that address the consideration and approval of any related person transactions. Under these Governance Guidelines, we may not enter into any transaction in which any Trustee or executive officer, any member of the immediate family of any Trustee or executive officer or any other related person, has or will have a direct or indirect material interest unless that transaction has been disclosed or made known to our Board and our Board reviews and approves or ratifies the transaction by the affirmative vote of a majority of the disinterested Trustees, even if the disinterested Trustees constitute less than a quorum. If there are no disinterested Trustees, the transaction must be reviewed and approved or ratified by both (1) the affirmative vote of a majority of our entire Board and (2) the affirmative vote of a majority of our Independent Trustees. The Governance Guidelines further provide that, in determining whether to approve or ratify a transaction, our Board, or disinterested Trustees or Independent Trustees, as the case may be, shall act in accordance with any applicable provisions of our declaration of trust, consider all of the relevant facts and circumstances and approve only those transactions that are fair and reasonable to us. All related person transactions described below were reviewed and approved or ratified by a majority of the disinterested Trustees or otherwise in accordance with our policies described above. In the case of transactions with us by RMR employees (other than our Trustees and executive officers) subject to our Code of Business Conduct and Ethics, the employee must seek approval from an executive officer who has no interest in the matter for which approval is being requested.

        We have no employees. Personnel and various services we require to operate our business are provided to us by RMR. We have two agreements with RMR to provide management and administrative services to us: (1) a business management agreement, which relates to our business generally, and (2) a property management agreement, which relates to our property level operations.

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        RMR has approximately 820 employees. One of our Managing Trustees, Mr. Barry Portnoy, is Chairman, majority owner and an employee of RMR. Our other Managing Trustee, Mr. Adam Portnoy, is the son of Mr. Barry Portnoy, and an owner, President, Chief Executive Officer and a director of RMR. Each of our executive officers is also an officer of RMR. CWH's executive officers are officers of RMR. Our Independent Trustees also serve as independent directors or independent trustees of other public companies to which RMR provides management services. Mr. Barry Portnoy serves as a managing director or managing trustee of those companies, including CWH, and Mr. Adam Portnoy serves as a managing trustee of a majority of those companies, including CWH. In addition, officers of RMR serve as officers of those companies. We understand that further information regarding those relationships is provided in the applicable periodic reports and proxy statements filed by those other companies with the SEC.

        Our Board has given our Compensation Committee, which is comprised exclusively of our Independent Trustees, authority to act on our behalf with respect to our management agreements with RMR. The charter of our Compensation Committee requires the Committee annually to review the terms of these agreements, evaluate RMR's performance under the agreements and renew, amend, terminate or allow to expire the management agreements.

        Our business management agreement with RMR provides for payment to RMR of a business management fee at annual rate equal to (a) with respect to the properties transferred to us by CWH or another REIT to which RMR provides business management or property management services, or an RMR Managed REIT, 0.5% of the historical cost of such properties to CWH or the RMR Managed REIT (accordingly, the business management fee we pay to RMR in respect of the properties so transferred would be expected to correspond to the reduction in the similar business management fee that CWH or the RMR Managed REIT pays to RMR, such that RMR would not be expected to receive an increase in the business management fees payable in aggregate by us and CWH or the RMR Managed REIT in respect of the transferred properties), plus (b) with respect to other properties we acquire, (i) 0.7% of our aggregate cost of those properties up to and including $250.0 million , plus (ii) 0.5% of our aggregate cost of those properties in excess of $250.0 million. In addition, beginning with the year ending December 31, 2013, RMR receives an incentive fee equal to 15% of the product of (i) the weighted average of our common shares outstanding on a fully diluted basis during a fiscal year and (ii) the excess if any of the Normalized FFO Per Share, as defined in the business management agreement, for such fiscal year over the Normalized FFO Per Share for the preceding fiscal year. The incentive fee is paid in our common shares and in any year shall not exceed $0.02 multiplied by the weighted average number of our common shares outstanding on a fully diluted basis during such fiscal year. Our common shares for these purposes are valued at the average closing prices of our common shares as reported on the NYSE during the month of December of the fiscal year to which the incentive fee pertains. The business management agreement also provides that, with certain exceptions, if we determine to offer for sale or other disposition any real property that, at such time, is of a type within the investment focus of another RMR Managed REIT, we will first offer that property for purchase or disposition to that RMR Managed REIT and negotiate in good faith for such purchase or disposition. The business management fees we paid to RMR for the period beginning on March 12, 2012, the date on which we entered into the agreement, through December 31, 2012, were $4.7 million.

        Our property management agreement with RMR provides for management fees equal to 3.0% of gross collected rents and construction supervision fees equal to 5.0% of construction costs. The aggregate property management and construction supervision fees we paid to RMR for the period

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beginning on March 12, 2012, the date on which we entered into the agreement, through December 31, 2012, were $3.0 million.

        RMR also provides internal audit services to us in return for our share of the total internal audit costs incurred by RMR for us and other publicly owned companies managed by RMR and its affiliates, which amounts are subject to approval by our Compensation Committee. Our Audit Committee appoints our Director of Internal Audit. Our share of RMR's costs of providing this internal audit function was approximately $0.2 million for 2012. These allocated costs are in addition to the business and property management fees we paid to RMR.

        We are generally responsible for all of our operating expenses, including certain expenses incurred by RMR on our behalf. We are not responsible for payment of RMR's employment, office or administration expenses incurred to provide management services to us, except for the employment and related expenses of RMR employees who provide on-site property management services and our pro rata share of the staff employed by RMR who perform our internal audit function. Pursuant to our business management agreement, RMR may from time to time negotiate on our behalf with certain third party vendors and suppliers for the procurement of services to us. As part of this arrangement, we may enter agreements with RMR and other companies to which RMR provides management services for the purpose of obtaining more favorable terms from such vendors and suppliers.

        Both our business management agreement with RMR and our property management agreement with RMR currently expire on December 31, 2013 and automatically renew for successive one year terms unless we or RMR give notice of non-renewal before the end of an applicable term. We or RMR may terminate either agreement upon 60 days' prior written notice, and RMR may also terminate either agreement upon five business days' notice if we undergo a change of control, as defined in the applicable agreement. On December 12, 2012, we entered amendments to these agreements, which clarified certain currently existing policies in the business management agreement and changed certain procedures for the arbitration of disputes pursuant to these agreements.

        Under our business management agreement with RMR, we acknowledge that RMR also provides management services to other companies, including CWH, and will not be required to present us with opportunities to invest in properties that are primarily of a type that are within the investment focus of another business now or in the future managed by RMR and that, in the event of conflict between us and any such other company, RMR shall in its discretion determine on which party's behalf it shall act.

        Under our share award plan, we have granted restricted shares to certain employees of RMR, some of whom are our officers. In 2012, we granted a total of 22,592 restricted shares with an aggregate value of $0.6 million to such persons, based upon the closing price of our common shares on the NYSE on the date of grant. One fifth of those restricted shares vested on the grant date and one fifth vests on each of the next four anniversaries of the grant date. These share grants to RMR employees are in addition to the fees we pay to RMR. On occasion, we have entered into arrangements with former employees of RMR in connection with the termination of their employment with RMR, providing for the acceleration of vesting of restricted shares previously granted to them under our share award plan.

        We were formerly a 100% owned subsidiary of CWH. CWH is our largest shareholder and, as of the date of this proxy statement, CWH owns 22,000,000 of our common shares, or approximately 56.0% of our outstanding common shares. One of our Managing Trustees, Mr. Barry Portnoy, is a managing trustee of CWH. Our other Managing Trustee, Mr. Adam Portnoy, is a managing trustee and the

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President of CWH. In addition, Mr. John Popeo, our Treasurer and Chief Financial Officer, also serves as the treasurer and chief financial officer of CWH, and one of our Independent Trustees, Mr. William Lamkin, is an independent trustee of CWH.

        In March 2012, we completed our IPO of 9,200,000 of our common shares (including 1,200,000 common shares sold pursuant to the full exercise of the underwriters' over allotment option) for net proceeds (after deducting underwriters' discounts and commissions and estimated expenses) of $180.8 million. We applied those net proceeds, along with proceeds of our initial borrowings under our $500.0 million revolving credit facility, to repay in full the $400.0 million demand promissory note that we issued to CWH in connection with CWH's contribution of 251 properties to us, or the Initial Properties, and to reimburse CWH for costs that CWH incurred in connection with our organization and preparation for our IPO.

        In connection with our IPO, we and CWH entered into a transaction agreement that governs our separation from and relationship with CWH. The transaction agreement provides that, among other things, (1) the current assets and liabilities of the Initial Properties, as of the time of closing of the IPO, were settled between us and CWH so that CWH will retain all pre-closing current assets and liabilities and we will assume all post-closing current assets and liabilities and (2) we will indemnify CWH with respect to any liability relating to any property transferred by CWH to us, including any liability which relates to periods prior to our formation, other than the pre-closing current assets and current liabilities that CWH retained with respect to the Initial Properties.

        In May 2012, we purchased 20,000 shares of common stock of Affiliates Insurance Company, or AIC, an Indiana insurance company, for approximately $5.3 million. Concurrently with this purchase, we entered into an amended and restated shareholders agreement, or the Shareholders Agreement, with AIC, RMR, CWH and five other companies to which RMR provides management services. We, RMR, CWH and five other companies to which RMR provides management services each currently own 12.5% of AIC. All of our Trustees, all of the trustees and directors of the other publicly held AIC shareholders and nearly all of the directors of RMR currently serve on the board of directors of AIC. RMR provides management and administrative services to AIC pursuant to a management and administrative services agreement with AIC. Our Governance Guidelines provide that any material transaction between us and AIC shall be reviewed, authorized and approved or ratified by the affirmative votes of a majority of our entire Board and a majority of our Independent Trustees. The shareholders agreement among us, the other shareholders of AIC and AIC includes arbitration provisions for the resolution of disputes.

        For the period from May 21, 2012 to December 31, 2012, we recognized income of $0.3 million related to our investment in AIC. We and the other shareholders of AIC have purchased property insurance providing $500.0 million of coverage pursuant to an insurance program arranged by AIC and with respect to which AIC is a reinsurer of certain coverage amounts. This program was entered into in June 2012 for a one year term, and we paid a premium, including taxes and fees, of $0.3 million, which amount may be adjusted from time to time as we acquire or dispose of properties that are included in this program. We are also currently investigating the possibilities to expand our insurance relationships with AIC to include other types of insurance. We may invest additional amounts in AIC in the future if the expansion of this insurance business requires additional capital, but we are not obligated to do so. By participating in this insurance business with RMR and the other companies to which RMR provides management services, we expect that we may benefit financially by possibly reducing our insurance expenses or by realizing our pro rata share of any profits of this insurance business.

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        The foregoing descriptions of our agreements with RMR, CWH and AIC are summaries and are qualified in their entirety by the terms of the agreements. A further description of the terms of certain of those agreements is included in our annual report to shareholders and our Annual Report on Form 10-K filed with the SEC, in each case for the year ended December 31, 2012. In addition, copies of certain of the agreements evidencing these relationships are filed with the SEC and may be obtained from the SEC's website at www.sec.gov.

        We believe that our agreements with RMR, CWH and AIC are on commercially reasonable terms. We also believe that our relationships with RMR, CWH and AIC and their affiliated and related persons and entities benefit us and, in fact, provide us with competitive advantages in operating and growing our business.

COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION

        Our Compensation Committee is currently comprised of Messrs. Lamkin and Somers and Ms. Fraiche. None of the members of our Compensation Committee is, or has been, an officer or employee of our Company. None of our executive officers serves on the board of directors (or related governing body) or compensation committee of another entity that has an executive officer who serves on our Board or Compensation Committee. Members of our Compensation Committee serve as independent trustees or independent directors and compensation committee members of other public companies managed by or affiliated with RMR.

SECTION 16(A) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

        Section 16(a) of the Exchange Act requires that our executive officers, Trustees and persons who own more than 10% of a registered class of our equity securities file reports of ownership and changes in ownership of securities with the SEC and the NYSE. Our executive officers, Trustees and greater than 10% shareholders are required to furnish us with copies of all forms they file pursuant to Section 16(a). Based solely on a review of the copies of these reports furnished to us or written representations made to us that no such reports were required, we believe that, during 2012, all filing requirements under Section 16(a) of the Exchange Act applicable to our executive officers, Trustees and persons who own more than 10% of a registered class of our equity securities were timely met except Mr. David Blackman, Mr. John Popeo and CWH each filed a late Form 3 in connection with the SEC declaring our registration statement effective on March 6, 2012.

HOUSEHOLDING OF ANNUAL MEETING MATERIALS

        Some banks, brokers and other record holders of our common shares may participate in the practice of "householding" proxy statements, annual reports and Notices of Internet Availability of those documents. This means that, unless shareholders give contrary instructions, only one copy of our proxy statement, annual report or Notice of Internet Availability may be sent to multiple shareholders in each household. We will promptly deliver a separate copy of any of those documents to you if you write to us at Investor Relations, Select Income REIT, Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458, or call us at (617) 796-8320. If you want to receive separate copies of our proxy statement, annual report or Notice of Internet Availability in the future, or if you are receiving multiple copies and would like to receive only one copy per household, you should contact your bank, broker or other record holder, or you may contact us at the above address or telephone number.

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OTHER MATTERS

        At this time, we know of no other matters that will be brought before the meeting. If, however, other matters properly come before the meeting or any postponement or adjournment thereof, the persons named in the accompanying proxy will vote the proxy in accordance with their discretion on such matters to the maximum extent that they are permitted to do so by applicable law.

February 25, 2013

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IMPORTANT

        If your shares are held in your own name, please complete a proxy over the internet or by telephone in the manner provided on the website indicated in the Notice of Internet Availability that you received in the mail; alternatively, please request, complete and return a proxy card today. If your shares are held in "street name," you should provide instructions to your broker, bank, nominee or the other institution holding your shares on how to vote your shares. You may provide instructions to your broker, bank, nominee or other institution over the internet or by telephone if your broker, bank, nominee or other institution offers these options, or you may return a proxy card to your broker, bank, nominee or other institution and contact the person responsible for your account to ensure that a proxy is voted on your behalf.

        If you have any questions or need assistance in voting your shares, please call the firm assisting us in the solicitation of proxies:

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, New York 10022
Brokers and Banks Call Collect at (212) 750-5833
Shareholders Call Toll-Free at (877) 717-3922

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QuickLinks

INTRODUCTION
PROPOSALS 1 AND 2 ELECTION OF TRUSTEES
PROPOSAL 3 RATIFICATION OF APPOINTMENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
SOLICITATION OF PROXIES
TRUSTEES AND EXECUTIVE OFFICERS
BOARD OF TRUSTEES
BOARD COMMITTEES
COMMUNICATIONS WITH TRUSTEES
SELECTION OF CANDIDATES FOR TRUSTEES; SHAREHOLDER RECOMMENDATIONS, NOMINATIONS AND OTHER PROPOSALS
COMPENSATION TABLES
SUMMARY COMPENSATION TABLE FOR 2012
OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END FOR 2012 (Shares granted in 2012, which have not yet vested)
POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL
TRUSTEE COMPENSATION FOR 2012 (2012 compensation; all share grants to Trustees vest at the time of grant)
AUDIT COMMITTEE REPORT
SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT
RELATED PERSON TRANSACTIONS AND COMPANY REVIEW OF SUCH TRANSACTIONS
COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION
SECTION 16(A) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE
HOUSEHOLDING OF ANNUAL MEETING MATERIALS
OTHER MATTERS
IMPORTANT