6-K

FORM 6-K

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16

under the Securities Exchange Act of 1934

For the month of April, 2023

001-14832

(Commission File Number)

CELESTICA INC.

(Translation of registrant’s name into English)

5140 Yonge Street, Suite 1900

Toronto, Ontario

Canada M2N 6L7

(416) 448-5800

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

Indicate by check mark whether the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ¨

Indicate by check mark whether the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ¨

Furnished Herewith (and incorporated by referenceherein)

The information contained in Exhibit 99.1 of this Form 6-K is not incorporated by reference into any registration statement (or into any prospectus that forms a part thereof) filed by Celestica Inc. with the Securities and Exchange Commission.

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.

Date: April 27, 2023

EXHIBIT INDEX

Exhibit 99.1

Celestica Inc.

Annual Meeting of Shareholders

April 27, 2023

REPORT OF VOTING RESULTS

National Instrument 51-102 – ContinuousDisclosure Obligations

Section 11.3

Matters Voted Upon