Company: TSLTF
Filing Date: 2025-12-12
Form Type: SUPPL
Source: 0001193125-25-317786
Chunk: 2

Company: TRANSALTA CORP
Filing Date: 2025-12-12
Form: SUPPL
Chunk 2
---
| Underwriting Commission(2)  |     |          |   1.25 | % |     | US$   |   5,000,000 |
| Proceeds to TransAlta(1)(3) |     |          | 98.135 | % |     | US$   | 392,540,000 |

| (1) | The public offering price set forth above does not include accrued interest, if any. |

| (2) | We refer you to “Underwriting” beginning on page S-51 of this Prospectus Supplement for 
 additional information regarding underwriting compensation.                             |

| (3) | Before deducting the expenses of the offering, which are estimated to be approximately US$1.5 million. |

The Notes will constitute a new issue of securities. There is no market through which Notes may be sold and purchasers may not be able to resell Notes purchased under this Prospectus Supplement. This may affect the pricing of the Notes in the secondary market, the transparency and availability of trading prices, the liquidity of the Notes, and the extent of issuer regulation. In addition, we do not intend to apply for listing of the Notes on any securities exchange. See “ Risk Factors ” in this Prospectus Supplement and in the Prospectus. THE NOTES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE UNITED STATES SECURITIES AND EXCHANGE COMMISSION (THE “SEC”) OR ANY UNITED STATES STATE SECURITIES COMMISSION NOR HAS THE SEC OR ANY UNITED STATES STATE SECURITIES COMMISSION PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS SUPPLEMENT OR THE PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE. This Prospectus Supplement qualifies the distribution of the Notes in each of the provinces of Canada solely for the purpose of registering the Notes in the United States pursuant to the multijurisdictional disclosure system adopted by the United States. This Prospectus Supplement does not qualify the Notes for distribution to purchasers in Canada, or to residents of Canada. See “ Underwriting – Offering Restrictions ”. This offering is made by a Canadian issuer that is permitted, under the multijurisdictional disclosure system adopted by the United States, to prepare this Prospectus Supplement and the Prospectus in accordance with Canadian disclosure requirements. Prospective investors should be aware that such disclosure requirements are different from those of the United States. The financial statements included herein have been prepared in accordance with International Financial Reporting