UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 6-K

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16 of

the Securities Exchange Act of 1934

For the month of: December 2025

Commission File Number: 1-14830

GILDAN ACTIVEWEAR INC.

(Translation of registrant’s name into English)

600 de Maisonneuve Boulevard West

33rd Floor

Montréal, Québec

Canada H3A 3J2

(Address of principal executive offices)

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 x

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.

	GILDAN ACTIVEWEAR INC.

Date: December 1, 2025	By:	/s/ Isabelle Papillon
		Name: Isabelle Papillon
		Title: Corporate Secretary

EXHIBIT INDEX

Exhibit		Description of Exhibit

99.1		Second Supplemental Indenture, dated as of December 1, 2025, between Gildan Activewear Inc., the guarantors party thereto and U.S. Bank Trust Company, National Association, as Trustee

Gildan Activewear Inc. 6-K