UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.     )

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Equity Commonwealth
(Name of Registrant as Specified In Its Charter)
(Name of Person(s) Filing Proxy Statement, if other than the Registrant)
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*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Shareholder Meeting to Be Held on June 20, 2018. EQUITY COMMONWEALTH You are receiving this communication because you hold shares in the company named above. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of EQUITY COMMONWEALTH TWO NORTH RIVERSIDE PLAZA SUITE 2100 CHICAGO, IL 60606 the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. proxy materials and voting instructions. E43817-P07505 See the reverse side of this notice to obtain Meeting Information Meeting Type:Annual Meeting For holders as of:April 16, 2018 Date: June 20, 2018Time: 8:00 a.m. Central Time Location: Two North Riverside Plaza Chicago, IL 60606

Before You Vote How to Access the Proxy Materials Have the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX (located on the by the arrow XXXX XXXX XXXX XXXX (located on the following page) in the subject line. How To Vote Please Choose One of the Following Voting Methods marked by the arrow XXXX XXXX XXXX XXXX (located on the following page) available and follow the instructions. E43818-P07505 Vote In Person: Many shareholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares. Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the information that is printed in the box Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card. Proxy Materials Available to VIEW or RECEIVE: ANNUAL REPORTPROXY STATEMENT How to View Online: following page) and visit: www.proxyvote .com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET: www.proxyvote.com 2) BY TELEPHONE: 1-800-579-1639 3) BY E-MAIL*: sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before June 6, 2018 to facilitate timely delivery.

Our Board of Trustees Recommends You Vote "FOR" the Nominees for Trustee in Proposal 1 and "FOR" Proposals 2 and 3. 1. To elect the nominees named in our proxy statement to our Board of Trustees 01) Sam Zell 02) James S. Corl 03) Martin L. Edelman 04) Edward A. Glickman 05) David Helfand 06) Peter Linneman 07) James L. Lozier, Jr. 08) Mary Jane Robertson 09) Kenneth Shea 10) Gerald A. Spector 11) James A. Star Our Board recommends you vote "FOR" Proposal 1. 2. To approve, on a non-binding advisory basis, the compensation of our named executive officers. Our Board recommends you vote "FOR" 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, 2018. Our Board recommends you vote "FOR" Proposal 3. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, THE PROXIES, IN THEIR DISCRETION, ARE AUTHORIZED TO VOTE UPON SUCH OTHER MATTERS AS MAY PROPERLY COME BEFORE THE MEETING OR AT ANY POSTPONEMENT OR ADJOURNMENT THEREOF. E43819-P07505 Voting Items

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