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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 6-K

Report of Foreign Private Issuer
Pursuant to Rule 13a-16 or 15d-16 of
the Securities Exchange Act of 1934

For the month of March 2005

001-14832
(Commission File Number)

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CELESTICA INC.
(Translation of registrant's name into English)

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1150 Eglinton Avenue East
Toronto, Ontario
Canada, M3C 1H7
(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):                              

Indicate by check mark whether by furnishing the information contained in this Form, is the registrant also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

If "Yes" is marked, indicate below the file number assigned to the registrant in connection with
Rule 12g3-2(b): 82-                             

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Celestica Inc.
Form 6-K
Month of March 2005

        The following information filed with this Form 6-K shall not be deemed incorporated by reference in Celestica Inc.'s registration statements, the prospectuses included therein, nor any registration statement subsequently filed by Celestica with the Securities and Exchange Commission:

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Press Release, dated March 21, 2005, the text of which is attached hereto as Exhibit 99.1, regarding Celestica Inc.'s option exchange program.

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Interim Financial Statements Request Form sent to shareholders on March 21, 2005, the text of which is attached hereto as Exhibit 99.2.

Exhibits
99.1		—		Press Release, dated March 21, 2005
99.2		—		Interim Financial Statements Request Form

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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.

		CELESTICA INC.
Date: March 21, 2005
		By:	/s/  ELIZABETH L. DELBIANCO       Elizabeth L. DelBianco Chief Legal Officer

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EXHIBIT INDEX

99.1		—		Press Release, dated March 21, 2005
99.2		—		Interim Financial Statements Request Form

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Exhibit 99.1

FOR IMMEDIATE RELEASE		March 21, 2005

CELESTICA INTENDS TO OFFER OPTION EXCHANGE PROGRAM

Proposed Program to be Offered to Eligible Employees Under
Company's Long-Term Incentive Plan

TORONTO, Ontario — Celestica Inc. (NYSE: CLS, TSX: CLS/SV), a world leader in electronics manufacturing services (EMS), today announced that it has filed with the SEC and Canadian securities regulators, and mailed to shareholders, the management information circular for its annual and special meeting of shareholders to be held on April 21, 2005.

The circular discloses that Celestica is seeking shareholder approval at the meeting for a proposed voluntary option exchange program that would permit eligible employees to surrender certain out-of-the-money options for US$1.00 in cash per option surrendered. Options with an exercise price of US$30 or greater, or Cdn.$40 or greater for Canadian dollar-denominated options, would be eligible for purposes of the program. Members of Celestica's board of directors, the chief executive officer, the chief financial officer, the president, option holders who retire on or prior to March 31, 2005 and employees who cease to be employed by Celestica prior to the date of the offer to purchase, would not be eligible to participate in the program. As at February 21, 2005, there were outstanding options to purchase 8,076,450 subordinate voting shares that satisfied these eligibility requirements. The US$1.00 purchase price that would be paid under the option exchange program represents approximately a one-third discount to the average estimated present value of the eligible options as at February 1, 2005. Further information regarding the proposed program is set out in the circular.

Celestica is proposing to undertake the option exchange program as part of a reorganization of its long-term incentive plans to provide more effective equity-based incentive arrangements to employees and to reduce market overhang associated with its out-of-the-money options.

In connection with the option exchange program, shareholders at the meeting will also be asked to approve amendments to Celestica's Long-Term Incentive Plan to limit the number of options and other rights that may be granted annually to 1.2% of the outstanding voting shares from time to time, to prohibit option grants to directors and to prohibit option repricings.

If the option exchange program is approved by shareholders at the meeting, Celestica expects to send a tender offer statement with details of the option exchange program, and provide instructions for the tender of eligible options, to eligible option holders in June 2005, and to complete the option exchange program in July 2005.

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Celestica has not commenced the option exchange program. Holders of the company's options are strongly advised to read the tender offer statement on Schedule TO and other documents to be filed with the Securities and Exchange Commission in connection with the option exchange program when they become available, as the documents will contain important information. When these documents are filed with the Securities and Exchange Commission, holders of Celestica options and others may obtain copies of these documents, without charge, at the Securities and Exchange Commission website located at www.sec.gov or by calling Celestica's Investor Relations department at 416-448-2211.

About Celestica

Celestica is a world leader in the delivery of innovative electronics manufacturing services (EMS). Celestica operates a highly sophisticated global manufacturing network with operations in Asia, Europe and the Americas, providing a broad range of integrated services and solutions to leading OEMs (original equipment manufacturers). Celestica's expertise in quality, technology and supply chain management, and leadership in the global deployment of Lean principles, enables the company to provide competitive advantage to its customers by improving time-to-market, scalability and manufacturing efficiency.

For further information on Celestica, visit its website at www.celestica.com.

The company's security filings can also be accessed at www.sedar.com and www.sec.gov.

Safe Harbour and Fair Disclosure Statement

This news release contains forward-looking statements related to our future growth, trends in our industry and our financial and operational results and performance that are based on current expectations, forecasts and assumptions involving risks and uncertainties that could cause actual outcomes and results to differ materially. These risks and uncertainties include, but are not limited to: the challenges of effectively managing our operations during uncertain economic conditions; the challenge of responding to lower-than-expected customer demand; the effects of price competition and other business and competitive factors generally affecting the EMS industry; our dependence on the computer and communications industries; our dependence on a limited number of customers and on industries affected by rapid technological change; component constraints; variability of operating results among periods; and the ability to manage expansion, consolidation and the integration of acquired businesses. These and other risks and uncertainties and factors are discussed in the Company's various public filings at www.sedar.com and http://www.sec.gov, including our Annual Report on Form 20-F and subsequent reports on Form 6-K filed with the Securities and Exchange Commission.

We disclaim any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

In the Company's best judgement, the events noted in this press release on a stand-alone basis are not expected to be material to Celestica's overall financial results.

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Celestica Contact:
Laurie Flanagan
Celestica Global Communications
(416) 448-2200
media@celestica.com

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QuickLinks

CELESTICA INTENDS TO OFFER OPTION EXCHANGE PROGRAM
Proposed Program to be Offered to Eligible Employees Under Company's Long-Term Incentive Plan

Exhibit 99.2

		CUSIP #15101Q108
INTERIM FINANCIAL STATEMENTS REQUEST

In accordance with applicable securities rules, beneficial shareholders may elect annually to have their name added to an issuer's supplemental mailing list in order to receive, at no cost to them, the issuer's interim financial statements or reports (including related management's discussion & analysis).

If you wish to receive the company's interim financial statements or reports, please complete and return this card to Computershare Trust Company of Canada at the address referred to on the reverse. If you choose not to receive the interim financial statements or reports, they will be available to you online at the same time they are mailed to shareholders at www.celestica.com/investor, www.sec.gov and www.sedar.com.

Name:

Street Address:

Suite #/Floor:

City/Town:

State/Province:

Postal/Zip Code:				Signature:
				(I certify that I am a beneficial shareholder)

This form is being sent to non-registered (beneficial) owners of securities. The company or its agent has sent this form directly to you. Your name and address and information about your securities have been obtained in accordance with applicable securities regulatory requirements from the intermediary holding on your behalf.

Privacy Notice
Computershare is committed to protecting your personal information. In the course of providing services to you and our corporate clients, we receive non-public personal information about you — from transactions we perform for you, forms you send us, other communications we have with you or your representatives, etc. This information could include your name, address, social insurance number, securities holdings and other financial information. We use this to administer your account, to better serve your and our client's needs and for other lawful purposes relating to our services. We have prepared a Privacy Code to tell you more about our information practices and how your privacy is protected. It is available at our website, www.computershare.com, or by writing us at 100 University Avenue, Toronto, Ontario, M5J 2Y1.

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CELESTICA INC. C/O COMPUTERSHARE TRUST COMPANY OF CANADA STOCK TRANSFER SERVICES 100 UNIVERSITY AVE., 9TH FLOOR TORONTO ON M5J 2Y1 CANADA

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