EQUITY COMMONWEALTH Two North Riverside Plaza, Suite 2100 Chicago, IL 60606 April 27, 2021 Dear Shareholder: You are cordially invited to the 2021 Annual Meeting of Shareholders of Equity Commonwealth. The Board of Trustees will hold the 2021 Annual Meeting of Shareholders in a virtual-only format in lieu of an in-person meeting to prioritize the health and well-being of meeting participants. At the Annual Meeting, you will be asked to (i) elect the 8 trustees named in our proxy materials to the Board of Trustees, (ii) approve, on a non-binding advisory basis, the compensation of our named executive officers, (iii) ratify the appointment of Ernst & Young LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2021, and (iv) transact such other business as may properly come before the Annual Meeting. The accompanying Notice of the Annual Meeting describes these matters. We have elected to provide access to our proxy materials on the Internet under the U.S. Securities and Exchange Commission’s ‘‘notice and access’’ rules, instead of mailing printed copies of those materials to each shareholder. Our proxy materials are available at www.proxyvote.com. We have sent to our shareholders a Notice of Internet Availability of Proxy Materials that provides instructions on how to access our proxy materials on the Internet. Please read the enclosed information carefully before submitting your proxy. The Board of Trustees appreciates and encourages your participation in the Annual Meeting. Regardless of whether you plan to attend the Annual Meeting, it is important that your shares be represented. Accordingly, please vote your shares by following the instructions contained in our proxy materials. If you do attend the Annual Meeting, you may withdraw your proxy and vote at the Annual Meeting. Sincerely, Sam Zell Chairman of the Board of Trustees EQUITY COMMONWEALTH Two North Riverside Plaza, Suite 2100 Chicago, IL 60606 NOTICE OF 2021 ANNUAL MEETING OF SHAREHOLDERS To be Held on June 23, 2021 To the Shareholders of Equity Commonwealth: NOTICE IS HEREBY GIVEN that the 2021 Annual Meeting of Shareholders, and any adjournments or postponements thereof (the ‘‘Annual Meeting’’), of Equity Commonwealth, a Maryland real estate investment trust (the ‘‘Company’’), will be held in a virtual-only format on June 23, 2021, at 9:00 a.m., Central Time. You will be able to attend the Annual Meeting, vote your shares electronically and submit your questions during the live webcast of the meeting by visiting www.virtualshareholdermeeting.com/EQC2021 and entering your control number included in the notice containing instructions on how to access Annual Meeting materials or your proxy card. The Annual Meeting will be held for the following purposes: 1. to elect the 8 trustees named in our proxy statement to the Board of Trustees (the ‘‘Board’’); 2. to approve, on a non-binding advisory basis, the compensation of our named executive officers; 3. to ratify the appointment of Ernst & Young LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2021; and 4. to transact such other business as may properly come before the Annual Meeting. The Board of Trustees will hold the 2021 Annual Meeting of Shareholders in virtual-only format in lieu of an in-person meeting to prioritize the health and well-being of meeting participants. Broadridge, a global proxy services firm, will host the virtual-only Annual Meeting. In order to participate in the virtual-only Annual Meeting, vote during the Annual Meeting and submit questions, please log into the meeting platform at: www.virtualshareholdermeeting.com/EQC2021. The virtual-only Annual Meeting will begin promptly at 9:00 a.m. Central Time, on June 23, 2021. Online access will begin at 8:45 a.m. Central Time. We encourage you to access the virtual-only Annual Meeting prior to the start time. Broadridge will have personnel ready to assist you with any technical difficulties you may have accessing the virtual-only Annual Meeting. Shareholders who hold their shares in ‘‘street name’’ through a broker or other financial institution or are registered shareholders may use the 16-digit control number and the instructions previously distributed to them to join the virtual-only Annual Meeting. We know of no other matters to come before the Annual Meeting. Only holders of record of common shares at the close of business on April 15, 2021 are entitled to notice of and to vote at the Annual Meeting or at any adjournments or postponements thereof. Regardless of the number of shares you hold, as a shareholder your role is very important, and the Board strongly encourages you to exercise your right to vote. Pursuant to the U.S. Securities and Exchange Commission’s ‘‘notice and access’’ rules, our Proxy Statement, proxy card and 2020 Annual Report to Shareholders are available online at www.proxyvote.com. We encourage you to contact the firm assisting us in the solicitation of proxies, D.F. King & Co., Inc. (‘‘D.F. King’’), if you have any questions or need assistance in voting your shares. Banks and brokers may call D.F. King collect at (212) 269-5550. Shareholders may call D.F. King toll-free at (877) 783-5524. By Order of the Board of Trustees, Orrin S. Shifrin April 27, 2021 Executive Vice President, Chicago, Illinois 60606 General Counsel and Secretary REGARDLESS OF WHETHER YOU PLAN TO ATTEND THE MEETING, YOU ARE URGED TO VOTE AT YOUR EARLIEST CONVENIENCE. IF YOU ATTEND THE MEETING, YOU MAY WITHDRAW YOUR PROXY AND VOTE AT THE ANNUAL MEETING. (This Page Intentionally Left Blank.) TABLE OF CONTENTS PROXY STATEMENT SUMMARY ................................................... 1 QUESTIONS AND ANSWERS ABOUT THE ANNUAL MEETING ......................... 6 PROPOSAL 1: ELECTION OF TRUSTEES ............................................. 10 Trustee Nominees . ................... 10 Vote Required and Recommendation . 14 PROPOSAL 2: ADVISORY VOTE ON EXECUTIVE COMPENSATION .................... 15 Vote Required and Recommendation . 15 PROPOSAL 3: RATIFICATION OF THE APPOINTMENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM ........................................ 16 Vote Required and Recommendation . 16 Principal Accountant Fees and Services. 16 Pre-Approval Policies and Procedures . 17 AUDIT COMMITTEE REPORT ................................................... 18 CORPORATE GOVERNANCE AND BOARD MATTERS ................................. 19 Corporate Governance Profile. 19 Board Leadership Structure. 19 Executive Sessions . 20 Attendance of Trustees at 2020 Board Meetings and Annual Meeting of Shareholders . 20 Committees of the Board . 20 Trustee Nominee Selection Process . 23 Board Oversight of Risk Management . 24 Corporate Governance Guidelines . 25 Code of Business Conduct and Ethics . 25 Sustainability and Social Responsibility. 26 Communications with the Board . 26 Compensation Committee Interlocks and Insider Participation. 26 EXECUTIVE OFFICERS ................................................... 27 COMPENSATION DISCUSSION AND ANALYSIS ....................................... 28 Compensation Overview . 28 Overview of Company Performance during 2020 . 28 Outperformance Over One, Three, and Five Years . 29 Compensation Objectives and Philosophy . 31 Compensation Snapshot . 31 Executive Compensation Program Highlights . 33 Compensation Determination Process . 34 Elements of Compensation . 35 Other Compensation Practices and Policies . 43 2021 Compensation Actions . 44 COMPENSATION COMMITTEE REPORT ............................................. 46 EXECUTIVE COMPENSATION ................................................... 47 Summary Compensation Table . 47 Grants of Plan-Based Awards . 48 Narrative Disclosure to Summary Compensation Table and Grants of Plan-Based Awards Table . 48 Outstanding Equity Awards at 2020 Fiscal Year-End . 49 Option Exercises and Stock Vested . 50 Potential Payments Upon Termination or Change in Control . 50 Pay Ratio Disclosure . 55 TRUSTEE COMPENSATION................................................... 56 Overview of Trustee Compensation Program . 56 Equity Awards Granted to Independent Trustees . 56 i Compensation for the Chairman of the Board . 57 Stock Ownership Guidelines. 58 Trustee Compensation Table for Fiscal Year 2020 . 58 EQUITY COMPENSATION PLAN INFORMATION...................................... 59 SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT . 60 Section 16(a) Beneficial Ownership Reporting Compliance . 61 CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS. 62 Review and Approval or Ratification of Transactions with Related Persons . 62 Related Person Transactions . 62 Indemnification . ................... 62 MISCELLANEOUS ................................................... 64 Other Matters to Come Before the Annual Meeting . 64 Shareholder Proposals and Nominations for the 2022 Annual Meeting of Shareholders . 64 Householding of Annual Meeting Materials . 64 IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR THE SHAREHOLDER MEETING TO BE HELD ON JUNE 23, 2021..................... 65 ii EQUITY COMMONWEALTH Two North Riverside Plaza, Suite 2100 Chicago, IL 60606 PROXY STATEMENT This.