As filed with the Securities and Exchange Commission on June 14, 2022

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM S-8

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

STAGWELL INC.

(Exact name of registrant as specified in its charter)

STAGWELL INC.

SECOND AMENDED AND RESTATED 2016 STOCK INCENTIVE PLAN

(Full title of the plan)

Frank Lanuto

Chief Financial Officer

Stagwell Inc.

One World Trade Center, Floor 65

New York, NY 10007

(Name and address of agent for service)

(646) 412-6857

(Telephone number, including area code, of agent for service)

Copies to:

Paul Tiger, Esq.

Andrea M. Basham, Esq.

Freshfields Bruckhaus Deringer US LLP

601 Lexington Avenue

New York, NY 10022

(212) 277-4000

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ¨

EXPLANATORY NOTE

This Registration Statement on Form S-8 is being filed for the purpose of registering an additional 15,000,000 shares of Class A common stock, par value $0.001 per share (the “Shares”), of Stagwell Inc. (the “Registrant”) pursuant to the Stagwell Inc. Second Amended and Restated 2016 Stock Incentive Plan (the “Plan”). In accordance with Section E of the General Instructions to Form S-8, the contents of the registration statement on Form S-8 previously filed by Registrant with the Securities and Exchange Commission (the “Commission”) on June 27, 2016 (File No. 333-212261) and on August 17, 2018 (File No. 333-226895) are incorporated by reference into this Registration Statement, except that the provisions contained in Part II of such previously-filed registration statement are modified as set forth in this Registration Statement.

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

The information specified in Item 1 and Item 2 of Part I of Form S-8 is not filed as part of this Registration Statement in accordance with the provisions of Rule 428 under the Securities Act of 1933, as amended (the “Securities Act”), and the introductory note to Part I of Form S-8.

Part II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

The following documents, which previously have been filed by the Registrant with the Commission, are incorporated herein by reference and made a part hereof:

(i) The Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (the “Annual Report”) (File No. 001-13718), filed by the Registrant with the Commission on March 17, 2022;

(ii) The information specifically incorporated by reference into the Annual Report from the Registrant’s definitive proxy statement on Schedule 14A (File No. 001-13718), filed by the Registrant with the Commission on May 2, 2022;

(iii) The Registrant’s Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2022 (File No. 001-13718), filed by the Registrant with the Commission on May 10, 2022;

(iv) The Registrant’s Current Reports on Form 8-K (File No. 001-13718), filed by the Registrant with the Commission on January 6, 2022 (solely with respect to Item 3.02 therein), March 24, 2022 (solely with respect to Item 8.01 therein) and March 28, 2022 (other than information furnished pursuant to Item 2.02 and Item 7.01 and any related exhibits of such Current Reports on Form 8-K, unless expressly stated otherwise herein or therein); and

(v) The description of the Registrant’s capital stock contained in the Registrant’s Current Report on Form 8-K12B (File No. 001-13718), filed by the Registrant with the Commission on July 30, 2021, as updated by Exhibit 4.3 to the Annual Report, together with any amendment or report filed for the purpose of updating such description.

All reports and other documents filed by the Registrant pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of this Registration Statement and prior to the filing of a post-effective amendment hereto that indicates that all securities offered hereunder have been sold or that deregisters all securities remaining unsold shall be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of filing of such documents.

For purposes of this Registration Statement, any statement contained in a document incorporated or deemed to be incorporated herein by reference shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed document that also is or is deemed to be incorporated herein by reference modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

Nothing in this Registration Statement shall be deemed to incorporate information furnished but not filed with the Commission pursuant to Item 2.02 or Item 7.01 of Form 8-K.

Not required to be filed with this Registration Statement in accordance with Section E of the General Instructions to Form S-8.

Not required to be filed with this Registration Statement in accordance with Section E of the General Instructions to Form S-8.

Not required to be filed with this Registration Statement in accordance with Section E of the General Instructions to Form S-8.

Not applicable.

Not required to be filed with this Registration Statement in accordance with Section E of the General Instructions to Form S-8.

SIGNATURES

Pursuant to the requirements of the Securities Act, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York, State of New York, on the 14th day of June, 2022.

POWER OF ATTORNEY

Each person whose signature appears below on this Registration Statement hereby constitutes and appoints Frank Lanuto and Edmund Graff with full power to act as his or her true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities (unless revoked in writing) to sign any and all amendments (including post-effective amendments thereto) to this Registration Statement to which this power of attorney is attached, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting to such attorney-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as full to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that such attorney-in-fact and agents, or their or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

This Power of Attorney may be executed in multiple counterparts, each of which shall be deemed an original, but which taken together shall constitute one instrument.

Pursuant to the requirements of the Securities Act, this Form S-8 Registration Statement has been signed by the following persons in the capacities and on the dates indicated.