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安大略省多倫多大學大道100號8樓M5J 2Y1 www.Computer Shar.com Mr A Sample 指定(如果有) add1 add2 add3 add4 add5 add6 000001安全級別 123持有人帳號 C1234567890 XXX 此代表是由TransAlta Corporation管理層並代表管理層徵求的。 備註 1.每位股東有權指定他們選擇的其他人或公司出席會議或其任何延期或延期,並代表他們行事。如果您希望委任的人或公司不是印刷在此的人,請在背面提供的空白處填寫您選擇的委託書持有人的姓名 ,並通過郵寄或互聯網投票的方式將您的委託書寄回www.investorvote.com。此外,您必須 在2024年4月23日美國東部夏令時上午11:00之前訪問www.ComputerShar.com/TransAlta,並向ComputerShare提供所選代理持有人的必需信息,以便ComputerShare可以通過電子郵件向代理持有人提供控制編號。此控制編號將允許您的代理持有人登錄會議並在會議上投票。 如果沒有控制編號,您的代理持有人將只能以來賓身份登錄會議,並且將無法投票。 2.如果股票以多個所有者的名義註冊(例如,共同所有權、受託人、遺囑執行人等),則所有註冊的人都應簽署此代理。如果您代表公司或其他個人投票,您可能需要提供文件,證明您有權以規定的簽署能力簽署本委託書。 3.本委託書的簽名方式應與委託書上的S(S)的姓名完全相同。 4.如果本委託書沒有註明日期,將被視為是TransAlta收到或代表TransAlta收到本表格的日期。 5.本委託書所代表的股份將按照股東的指示進行投票,但如果沒有就任何事項作出此類指示,並且背面點名的管理層被提名人是指定的代理人,則此委託書將按照TransAlta董事會的建議進行表決。 6.此委託書所代表的股份將根據股東的指示,在可能要求的任何投票中投贊成票,或保留投票權,或投反對票,如股東已就任何待採取行動的事項作出選擇,股份將據此投票。 7.本委託書授予對會議通知和管理委託書通告中確定的事項的修改或變更的自由裁量權,或 可在會議或其任何延期或延期之前適當提交的其他事項,除非法律禁止。 8.本委託書應與管理層提供的隨附文件一起閲讀,包括TransAlta的管理委託書。 委託書必須在2024年4月23日(星期二)上午11:00(山區時間)之前收到。 如果會議被推遲或延期,提交的委託書必須在48小時內收到 (不包括星期六,週日和法定節假日)重新召開會議。 每週7天、每天24小時使用電話或互聯網投票! 摺疊 ·通過按鍵電話撥打下面列出的號碼。 1-866-732-Vote(8683)免費 ·轉到以下網站: www.Invest orvote.com ·智能手機? 掃描二維碼 立即投票。 ·您可以註冊接收未來證券持有人 通過訪問 www.investorcentre.com進行電子通信。 ·您可以通過訪問此代理背面提供的URL來虛擬出席會議。 如果您通過電話或Internet進行投票,請勿郵寄此委託書。 郵寄投票可能是以公司名義持有的股份或代表其他個人投票的唯一方法。 股東可以通過郵寄或互聯網投票指定除此 委託書背面指定的管理層提名人以外的其他人作為代理人。您可以選擇上面列出的兩種投票方法之一來投票此代理,而不是郵寄此代理。 要通過電話或互聯網投票,您需要提供下面列出的控制編號。 控制編號 01YS2B 123456789012345 CPUQC01.E.INT/000001/i1234形式的代理-將於2024年4月25日(星期四)舉行的年度股東大會使用電話投票使用互聯網接收電子文件 以虛擬方式出席會議 24-5672-7 cp189

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MR SAM SAMPLE Appointment of Proxyholder I/We being holder(s) of securities of TransAlta Corporation (the”Company”) hereby appoint: OR John P. Dielwart, Chair of the Board, or failing this person, John H. Kousinioris, President and Chief Executive Officer C1234567890 XXX 123 Print the name of the person you are appointing (including yourself) if this person is someone other than theManagement nominees listed herein. Note: If you wish to appoint a person (including yourself) or company other than the persons whose names are printed herein, please insert the name of your chosen proxyholder in the space provided on the reverse and return your proxy by mail or vote by Internet at www.investorvote.com. In addition, YOU MUST go to www.Computershare.com/TransAlta by 11:00 am (MDT) on April 23, 2024, and provide Computershare with the required information for your chosen proxyholder so that Computershare may provide the proxyholder with a Control Number via email. This Control Number will allow your proxyholder to log into and vote at the meeting. Without a Control Number your proxyholder will only be able to log in to the meeting as a guest and will not be able to vote. as my/our proxyholder with full power of substitution and to attend, act and to vote for and on behalf of the shareholder(s) in accordance with the following direction (or if no directions have been given, as the proxyholder sees fit) and on all other matters that may properly come before the Annual General Meeting (the “Meeting”) of shareholders of the Company to be held via live audio webcast online at https://web.lumiagm.com/471294222 on Thursday, April 25, 2024 at 11:00 am (Mountain Time) and at any adjournment or postponement thereof. The Board of Directors recommends voting “FOR” Items 1, 2 and 3. VOTING RECOMMENDATIONS ARE INDICATED BY HIGHLIGHTED TEXT OVER THE BOXES. 1. Election of Directors 01. John P. Dielwart For Against 07. Thomas M. O’Flynn For Against Fold 02. Alan J. Fohrer 08. Bryan D. Pinney 03. Laura W. Folse 09. James Reid 04. Harry A. Goldgut 05. John H. Kousinioris 10. Manjit K. Sharma 11. Sandra R. Sharman 06. Candace J. MacGibbon 12. Sarah A. Slusser For Withhold 2. Reappointment of Auditors Appointment of Ernst & Young LLP as auditors of the Company and authorize the directors to fix their remuneration. 3. Say-on-Pay Advisory vote to accept the Company’s approach to executive compensation, as described in the Management Proxy Circular. For Against Fold Authorized Signature(s) – This section must be completed for your instructions to be executed. I/We authorize you to act in accordance with my/our instructions set out above. I/We hereby revoke any proxy previously given with respect to the Meeting. If no voting instructions are indicated above and the Management nominees are appointed proxyholders, this proxy will be voted as recommended by the Board of Directors. Signature(s) Date MM / DD / YY Interim Financial Statements – I would like to receive interim financial statements and related Management’s Discussion & Analysis. Annual Financial Statements – I DO NOT wish to receive annual financial statements and related Management’s Discussion & Analysis. If you are not mailing back your proxy, you may register online to receive the above financial report(s) by mail at www.computershare.com/mailinglist. Z T M Q 363128 X X X X A R 2 999999999999 01YS3C 24-5672-7 C1.1 P190