[6-K] TRANSALTA CORP Current Report (Foreign Issuer)

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

For the month of December 2025

Commission File Number: 001-15214

TransAlta Corporation

(Translation of registrant’s name into English)

Suite 1400, 1100—1st Street S.E., Calgary, Alberta, T2G 1B1

(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 ☒

INCORPORATION BY REFERENCE

Exhibit 99.1 of this Form 6-K is incorporated by reference as an additional exhibit to the registrant’s Registration Statement on Form F-10 (File No. 333-292019).

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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.

						TransAlta Corporation
						(Registrant)
Date: December 11, 2025						/s/ Kelly Galloway
						Kelly Galloway
						Corporate Secretary

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EXHIBIT INDEX

Exhibit Number		Description
99.1		Consent of Ernst & Young LLP

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