UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

THOMSON REUTERS CORPORATION

(Translation of registrant’s name into English)

333 Bay Street, Suite 400

Toronto, Ontario M5H 2R2, Canada

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F  ☐            Form 40-F  ☒

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ☐

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: November 27, 2018

EXHIBIT INDEX

Exhibit 99.1

Thomson Reuters Announces Share Consolidation Ratio

for Return of Capital Transaction

Shares to begin trading tomorrow on the TSX and NYSE on a post-consolidated basis

TORONTO, November 26, 2018 – Thomson Reuters (TSX/NYSE: TRI) today announced the share consolidation ratio for its return of capital transaction which will be effective at 3:01 a.m. (Toronto time) tomorrow. The company’s common shares will begin trading on the Toronto Stock Exchange (TSX) and the New York Stock Exchange (NYSE) on a post-consolidated basis when markets open tomorrow. The company’s trading symbol will remain “TRI” on both exchanges. The new CUSIP number for the post-consolidated common shares is 884903709 and the new ISIN number is CA8849037095.

As of November 26, 2018, the company had 552,574,909 common shares issued and outstanding. When the return of capital transaction is effective and the shares are consolidated, the company will reduce the total number of its issued and outstanding common shares to 504,916,616.

Computershare Trust Company of Canada, the company’s depositary for the transaction, will deliver cash distribution amounts to registered participating shareholders as promptly as practicable, subject to the terms and conditions of the transaction. The effects of the share consolidation will be reflected in the company’s share register. Beneficial or non-registered shareholders participating in the transaction will receive cash distributions from their bank, broker or other intermediary and the effects of the share consolidation will be recorded in their accounts.

Fractional shares will not be issued as part of the return of capital transaction and shareholders will receive the value of any fractional shares in cash, subject to certain exceptions described in the management proxy circular.

As previously announced, the transaction is generally expected to be tax-free for Canadian tax purposes. A U.S. shareholder who has chosen to opt out of the transaction generally is not expected to be subject to U.S. federal income tax or Canadian federal income tax. A U.S. shareholder who participates in the transaction generally is expected to be subject to U.S. federal income tax on any gain realized and is not expected to be subject to Canadian federal income tax. The tax consequences of the proposed return of capital transaction are complex. This summary reflects certain assumptions and limitations and it is qualified in its entirety by the “Income Tax Considerations” section of the management proxy circular for the return of capital transaction.

The return of capital transaction is one of several ways that the company is returning US$10 billion of proceeds from its recently closed Financial & Risk transaction to its shareholders. Following the return of capital transaction, the company will have returned approximately US$9.8 billion of this amount. The company plans to complete the return of proceeds later this year through the repurchase of approximately US$200 million of its shares under its normal course issuer bid.

The full details of the return of capital transaction are described in the company’s management proxy circular dated October 16, 2018 and related materials, which are available on www.thomsonreuters.com in the “Investor relations” section. The return of capital documents were previously filed with the Canadian securities regulatory authorities on SEDAR and are available at www.sedar.com. The documents were also furnished to the U.S. Securities and Exchange Commission through EDGAR and are available at www.sec.gov.

Thomson Reuters Announces Share Consolidation Ratio for Return of Capital Transaction

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Thomson Reuters

Thomson Reuters (TSX/NYSE: TRI) is the world’s leading provider of news and information-based tools to professionals. Our worldwide network of journalists and specialist editors keep customers up to speed on global developments, with a particular focus on legal, regulatory and tax changes. Thomson Reuters shares are listed on the Toronto and New York Stock Exchanges. For more information on Thomson Reuters, visit tr.com and for the latest world news, reuters.com.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain statements in this news release are forward-looking, including statements relating to the timing of the return of capital transaction. These forward-looking statements are based on certain assumptions and reflect our company’s current expectations. As a result, forward-looking statements are subject to a number of risks and uncertainties that could cause actual results or events to differ materially from current expectations, including other factors discussed in materials that Thomson Reuters from time to time files with, or furnishes to, the Canadian securities regulatory authorities and the U.S. Securities and Exchange Commission. There is no assurance that the return of capital transaction will be completed or that other events described in any forward-looking statement will materialize. Except as may be required by applicable law, Thomson Reuters disclaims any obligation to update or revise any forward-looking statements.

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