TransAlta Corporation Announces Conversion Results for Series A and B Preferred Shares

CALGARY, Alberta, March 17, 2026 -- Further to TransAlta Corporation's (TransAlta or the Company) (TSX: TA) (NYSE: TAC) press release dated March 2, 2026, the Company announced today that none of its 9,629,913 currently outstanding Cumulative Redeemable Rate Reset First Preferred Shares, Series A (Series A Shares) will be converted on March 31, 2026, on a one-for-one basis, into Cumulative Redeemable Floating Rate First Preferred Shares, Series B (Series B Shares), and (ii) 1,148,549 of its 2,370,087 currently outstanding Series B Shares will be converted on March 31, 2026, on a one-for-one basis, into Series A Shares. As a result, on March 31, 2026, the Company will have 10,778,462 Series A Shares issued and outstanding and 1,221,538 Series B Shares issued and outstanding.

The Series A Shares and Series B Shares are currently listed on the Toronto Stock Exchange under the symbols TA.PR.D and TA.PR.E, respectively.

About TransAlta Corporation:

TransAlta is one of Canada’s largest publicly traded power generators, delivering reliable electricity across Canada, the United States and Western Australia. For more than 100 years, our people have safely operated and evolved essential energy infrastructure that powers customers and communities. Our technology-diverse portfolio and disciplined execution allow us to deliver dependable power across evolving energy systems. We take a practical, responsible approach to meeting today’s energy needs while building for what comes next.

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