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·完整,在 背面簽名並註明日期。 ·將此表格放入提供的 信封中返回。 ·您可以通過訪問 www.investorcentre.com以電子方式註冊接收未來的 安全持有人通信 。 ·訪問以下網站: www.investorvote.com ·智能手機? 掃描二維碼 立即投票。 ·您可以通過訪問URL以虛擬方式參加會議 此委託書背面提供。 01 VSEC 摺疊表 摺疊表 將於4月27日舉行的年度會議,2023年。 一週7天、每天24小時使用電話或互聯網投票。 如果您通過電話或互聯網投票,請勿郵寄此表。 只有郵寄或互聯網投票才是持有人指定代理人以外的人的唯一方法。 代理人表格背面指定的管理層被提名人除外。您可以選擇上述兩種投票方式中的一種來投票此委託書,而不是郵寄此委託書。 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 1.您有權指定其他人、公司或您選擇的其他法人實體(“被指定人”)出席年會或其任何續會或延期會議並代表您行事。如果您希望委任的人、公司或其他法人實體的姓名不在此列,請在所提供的空白處填寫您所選擇的被任命人的姓名(見背面)。此外,您必須訪問 https://www.computershare.com/Celestica並向ComputerShare提供所選被任命人的所需信息,以便ComputerShare可以通過電子郵件向 被任命者提供邀請碼。此邀請代碼將允許您的被任命人登錄並在年會上投票。如果沒有邀請代碼 您指定的人將只能以嘉賓身份登錄年會,並且不能投票。 2.如果證券是以多個所有者(例如,共同所有人、受託人、遺囑執行人等)的名義註冊的,則所有註冊的人都應在此委託書上簽名。 如果您代表公司、其他法人實體或其他個人投票,您必須在此委託書上簽名,並註明簽名能力,並且您可能需要提供 證明您有權簽署此委託書的文件。 3.此委託書的簽名方式應與委託書上的姓名(S)(S)完全相同。 4.如果此委託書沒有註明日期,它將被視為具有管理層郵寄給您的日期。 5.此委託書所代表的證券,在正確執行後,將根據您的指示投贊成票、反對票或棄權票,但是,如果您沒有就任何事項指示您的投票,並且您沒有指定指定的人作為您的委託持有人,則此委託書將被投票:用於選舉管理層提名的Celestica Inc.董事進入董事會;任命畢馬威有限責任公司為Celestica Inc.的審計師;授權Celestica Inc.董事會確定審計師的薪酬;6.本委託書授權酌情處理股東周年大會或其任何延會或延期的會議通告或其他事項。 7.本委託書應與股東周年大會通告及管理層資料通告一併閲讀。 遞交的委託書必須於上午9:30前收到。美國東部夏令時2023年4月25日,如果年會延期或延期,則在年會休會或延期前至少48小時,不包括星期六、星期日和法定節假日。 委託書須知 ·通過按鍵 電話撥打下列號碼。 多倫多大學大道100號8樓,安大略省M5J 2Y1 www.ComputerShar.com 投票使用 電話 投票使用 互聯網 虛擬出席 年會通過郵寄投票接收文件 電子 Sample先生 Samples街123 Samples Street SAMPLETOWN SS X9X 9X9安全等級 下屬投票股份 C1234567890 XXX 持有者帳號 CPUQC01.E.INT/000001/i1234 123456789012345 1-866-732-Vote(8683)

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348595 Fold Fold . AR1 If you are not mailing back your form of proxy, you may register online to receive the above financial report(s) by mail at www.computershare.com/mailinglist. Interim Financial Statements – Mark this box if you would like to receive Interim Financial Statements and accompanying Management’s Discussion and Analysis by mail. Annual Financial Statements – Mark this box if you would like to receive the Annual Financial Statements and accompanying Management’s Discussion and Analysis by mail. 01VSFB 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 form of proxy previously given with respect to the Annual Meeting. If no voting instructions are indicated above, this form of proxy will be voted as recommended by Management. DD . / MM / YY Signature(s) Date Appointment of Proxyholder Instead of either of the foregoing, print the name of the person you are appointing as an Appointee if this person is someone other than the Management Nominees listed herein. I/We, being holder(s) of Subordinate Voting Shares of Celestica Inc. hereby appoint: Michael M. Wilson or, failing him, Robert A. Mionis, or their designees (Management Nominees) OR as my/our proxyholder with full power of substitution and to attend, act and to vote in accordance with the following direction (or if no directions have been given, as the proxyholder sees fit) and to vote at the discretion of the proxyholder with respect to amendments or variations to matters identified in the Notice of Meeting or other matters that may properly come before the Annual Meeting of Shareholders of Celestica Inc. to be held virtually at https://meetnow.global/MR6KD4X on April 27, 2023 at 9:30 a.m., EDT and at any adjournments or postponements thereof. VOTING RECOMMENDATIONS OF MANAGEMENT ARE INDICATED BY HIGHLIGHTED TEXT OVER THE BOXES. Note: If completing the appointment box above YOU MUST go to http://www.computershare.com/Celestica and provide Computershare with the name and email address of the person you are appointing. Computershare will use this information ONLY to provide the Appointee with an Invitation Code to gain entry to and vote at the online meeting. This form of proxy is solicited by and on behalf of Management. 1. Election of Directors 4. Advisory resolution on Celestica Inc.’s approach to executive compensation For Against For Withhold For Withhold For Withhold 2. Appointment of auditor Appointment of KPMG LLP as auditor of Celestica Inc. For Withhold 3. Authority to fix the remuneration of the auditor Authorization of the Board of Directors of Celestica Inc. to fix the remuneration of the auditor. For Withhold 01. Robert A. Cascella 04. Daniel P. DiMaggio 07. Robert A. Mionis 02. Deepak Chopra 05. Jill Kale 08. Luis A. Müller 09. Tawfiq Popatia 03. Françoise Colpron 06. Laurette T. Koellner 10. Michael M. Wilson MR SAM SAMPLE 123 C1234567890 XXX CLSQ 999999999999