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 October, 2015

001-14832

(Commission File Number)

CELESTICA INC.

(Translation of registrant’s name into English)

844 Don Mills Road

Toronto, Ontario

Canada M3C 1V7

(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): o

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): o

Furnished Herewith (and incorporated by reference herein)

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.

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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.

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EXHIBIT INDEX

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Exhibit 99.1

CELESTICA ANNOUNCES THIRD QUARTER 2015 FINANCIAL RESULTS

TORONTO, Canada - Celestica Inc. (NYSE, TSX: CLS), a global leader in the delivery of end-to-end product lifecycle solutions, today announced financial results for the third quarter ended September 30, 2015.

Third Quarter 2015 Highlights

·                  Revenue: $1.41 billion, within our guidance range of $1.4 billion to $1.5 billion (announced July 23, 2015), relatively flat compared to the third quarter of 2014

·                  Revenue from our diversified end market represented 30% of total revenue, compared to 29% for the third quarter of 2014

·                  Operating margin (non-IFRS): 3.8%, compared to 3.9% for the third quarter of 2014

·                  Adjusted EPS (non-IFRS): $0.22 per share ($0.30 per share had we excluded an $0.08 per share income tax expense resulting from taxable foreign exchange impacts), compared to $0.26 per share for the third quarter of 2014. Had we excluded this income tax expense of $0.08 per share, adjusted EPS (non-IFRS) would have been within our guidance range of $0.28 to $0.34 per share (announced July 23, 2015).

·                  IFRS EPS: $0.08 per share (negatively impacted by the $0.08 per share income tax expense discussed above), compared to $0.19 per share for the third quarter of 2014

·                  ROIC (non-IFRS): 20.9%, compared to 21.3% for the third quarter of 2014

·                  Free cash flow (non-IFRS): $12.8 million, compared to $92.7 million for the third quarter of 2014

“Despite a challenging end market environment, Celestica delivered higher operating margin and return on invested capital compared to the second quarter of this year, based on our ongoing focus on continuous improvement and disciplined cost management,” said Robert Mionis, Celestica’s President and Chief Executive Officer.

 “Overall, we remain focused on our strategic objectives of expanding our business into more profitable markets leveraging our leadership in higher reliability applications, as well as driving continued improvements across our entire business in the areas of quality, profitability and free cash flow generation.”

Third Quarter and Year-to-Date Summary

more...

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(i)            International Financial Reporting Standards (IFRS) EPS and adjusted EPS (non-IFRS) for the three and nine months ended September 30, 2015, respectively, reflect an $0.08 per share income tax expense related to taxable foreign exchange impacts arising from the weakening of the Malaysian ringgit and Chinese renminbi relative to the U.S. dollar, $0.04 of which were deferred tax costs related to period-end revaluations of non-monetary balance sheet items. See note 11 to our September 30, 2015 unaudited interim condensed consolidated financial statements. IFRS EPS for the third quarter of 2015 included an aggregate charge of $0.15 (pre-tax) per share for employee stock-based compensation expense, amortization of intangible assets (excluding computer software) and restructuring charges. This aggregate charge is within the range we provided on July 23, 2015 of an aggregate charge of between $0.10 and $0.16 per share for these items (see the tables in Schedule 1 attached hereto for per-item charges).

(ii)         Non-IFRS measures do not have any standardized meaning prescribed by IFRS and therefore may not be comparable to similar measures presented by other public companies that use IFRS or other generally accepted accounting principles (GAAP). See “Non-IFRS Supplementary Information” below for information on our rationale for the use of non-IFRS measures, and Schedule 1 for, among other items, non-IFRS measures included in this press release, as well as their definitions, uses, and a reconciliation of non-IFRS to IFRS measures (where a comparable IFRS measure exists).

End Markets by Quarter as a Percentage of Total Revenue

(i)             Our diversified end market is comprised of aerospace and defense, industrial, healthcare, energy, and semiconductor equipment.

Fourth Quarter 2015 Outlook

For the fourth quarter ending December 31, 2015, we anticipate revenue to be in the range of $1.375 billion to $1.475 billion, and non-IFRS adjusted net earnings per share to be in the range of $0.27 to $0.33. We expect a negative $0.06 to $0.12 per share (pre-tax) aggregate impact on net earnings on an IFRS basis for employee stock-based compensation expense and amortization of intangible assets (excluding computer software).

Third Quarter 2015 Webcast

Management will host its third quarter 2015 results conference call today at 5:00 p.m. Eastern Daylight Time. The webcast can be accessed at www.celestica.com.

Non-IFRS Supplementary Information

In addition to disclosing detailed operating results in accordance with IFRS, Celestica provides supplementary non-IFRS measures to consider in evaluating the company’s operating performance. Management uses adjusted net earnings and other non-IFRS measures to assess operating performance and the effective use and allocation of resources; to provide more meaningful period-to-period comparisons of operating results; to enhance investors’ understanding of the core operating results of Celestica’s business; and to set management incentive targets. We believe investors use both IFRS and non-IFRS measures to assess past, current and future decisions associated with our priorities and our allocation of capital, as well as to analyze how our business operates in, or responds to, swings in economic cycles or to other events that impact our core operations. See Schedule 1 - Supplementary Non-IFRS Measures for, among other items, non-IFRS measures provided herein, non-IFRS definitions, and a reconciliation of non-IFRS to IFRS measures (where a comparable IFRS measure exists).

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About Celestica

Celestica is dedicated to delivering end-to-end product lifecycle solutions to drive our customers’ success. Through our simplified global operations network and information technology platform, we are solid partners who deliver informed, flexible solutions that enable our customers to succeed in the markets they serve. Committed to providing a truly differentiated customer experience, our agile and adaptive employees share a proud history of demonstrated expertise and creativity that provides our customers with the ability to overcome complex challenges. For further information about Celestica, visit our website at www.celestica.com. Our securities filings can also be accessed at www.sedar.com and www.sec.gov.

Cautionary Note Regarding Forward-looking Statements

This news release contains forward-looking statements related to our future growth; trends in the electronics manufacturing services (EMS) industry; our financial or operational results including our quarterly revenue and earnings guidance; the impact of acquisitions and program wins or losses on our financial results and working capital requirements; anticipated expenses, restructuring actions and charges, capital expenditures and/or benefits; our expected tax and litigation outcomes; our cash flows, financial targets and priorities; changes in our mix of revenue by end market; our ability to diversify and grow our customer base and develop new capabilities; the effect of the global economic environment on customer demand; expected investments in our solar business, the expected timing of ramping our solar programs in Asia, and the timing and extent of expected recovery of cash advances to a particular solar cell supplier; the impact of the financing of the SIB (as defined herein), including the impact of the Term Loan (as defined herein), on our liquidity, future operations and financial condition; the timing and terms of the sale of our real property in Toronto and related transactions, including the expected lease of our corporate head office (collectively, the “Toronto Real Property Transactions”); and, if the Toronto Real Property Transactions are completed, our ability to secure on commercially acceptable terms an alternate site for our existing Toronto manufacturing operations and the expected transition costs for such relocation. Such forward-looking statements may, without limitation, be preceded by, followed by, or include words such as “believes”, “expects”, “anticipates”, “estimates”, “intends”, “plans”, “continues”, “project”, “potential”, “possible”, “contemplate”, “seek”, or similar expressions, or may employ such future or conditional verbs as “may”, “might”, “will”, “could”, “should” or “would”, or may otherwise be indicated as forward-looking statements by grammatical construction, phrasing or context.  For those statements, we claim the protection of the safe harbor for forward-looking statements contained in the U.S. Private Securities Litigation Reform Act of 1995 and applicable Canadian securities laws.

Forward-looking statements are provided for the purpose of assisting readers in understanding management’s current expectations and plans relating to the future. Readers are cautioned that such information may not be appropriate for other purposes. Forward-looking statements are not guarantees of future performance and are subject to risks that could cause actual results to differ materially from conclusions, forecasts or projections expressed in such statements, including, among others, risks related to: our customers’ ability to compete and succeed in the marketplace with the services we provide and the products we manufacture; price and other competitive factors generally affecting the EMS industry; managing our operations and our working capital performance during uncertain market and economic conditions; responding to changes in demand, rapidly evolving and changing technologies, and changes in our customers’ business and outsourcing strategies, including the insourcing of programs; customer concentration and the challenges of diversifying our customer base and replacing revenue from completed or lost programs, or customer disengagements; changing commodity, material and component costs, as well as labor costs and conditions; disruptions to our operations, or those of our customers, component suppliers or logistics partners, including as a result of global or local events outside our control; retaining or expanding our business due to execution problems relating to the ramping of new programs or new offerings; the incurrence of future impairment charges; recruiting or retaining skilled personnel; current or future litigation and/or governmental actions; successfully resolving commercial and operational challenges, and improving financial results, in our semiconductor business; delays in the delivery and availability of components, services and materials; non-performance by counterparties; our financial exposure to foreign currency volatility; our dependence on industries affected by rapid technological change; the variability of revenue and operating results; managing our global operations and supply chain; increasing income taxes, tax audits, and defending our tax positions or meeting the conditions of tax incentives and credits; completing restructuring actions, including achieving the anticipated benefits therefrom, and integrating any acquisitions; computer viruses, malware, hacking attempts or outages that may disrupt our operations; any failure to adequately protect our intellectual property or the intellectual property of others; compliance with applicable laws, regulations and social responsibility initiatives; our having sufficient financial resources and working capital following completion of the SIB and consummation of the Term Loan to fund currently anticipated financial obligations and to pursue desirable business opportunities; the potential that conditions to closing the Toronto Real Property Transactions may not be satisfied on a timely basis or at all; and, if the Toronto Real Property Transactions are completed, our ability to secure on commercially acceptable terms an alternate site for our existing Toronto manufacturing operations, and the costs, timing and/or execution of such relocation proving to be other than anticipated. The foregoing and other material risks and uncertainties are discussed in our public filings at www.sedar.com and www.sec.gov, including in our MD&A, our Annual Report on Form 20-F filed with, and subsequent reports on Form 6-K furnished to, the U.S. Securities and Exchange Commission, and our Annual Information Form filed with the Canadian Securities Administrators.

Our revenue, earnings and other financial guidance, as contained in this press release, are based on various assumptions, many of which involve factors that are beyond our control. The material assumptions include those related to the following: production schedules from our customers, which generally range from 30 to 90 days and can fluctuate significantly in terms of volume and mix of products or services; the timing and execution of, and investments associated with, ramping new business; the success in the

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marketplace of our customers’ products; the stability of general economic and market conditions, currency exchange rates, and interest rates; our pricing, the competitive environment and contract terms and conditions; supplier performance, pricing and terms; compliance by third parties with their contractual obligations, the accuracy of their representations and warranties, and the performance of their covenants; the costs and availability of components, materials, services, plant and capital equipment, labor, energy and transportation; operational and financial matters including the extent, timing and costs of replacing revenue from completed or lost programs, or customer disengagements; technological developments; overall demand improvement in the semiconductor industry, revenue growth and improved financial results in our semiconductor business; the timing, execution and effect of restructuring actions; our having sufficient financial resources and working capital following completion of the SIB and consummation of the Term Loan to fund our currently anticipated financial obligations and to pursue desirable business opportunities; and our ability to diversify our customer base and develop new capabilities. While management believes these assumptions to be reasonable under the current circumstances, they may prove to be inaccurate. Except as required by applicable law, forward-looking statements speak only as of the date on which they are made and 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.

All forward-looking statements attributable to us are expressly qualified by these cautionary statements.

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Schedule 1

Supplementary Non-IFRS Measures

Our non-IFRS measures herein include adjusted gross profit, adjusted gross margin (adjusted gross profit as a percentage of revenue), adjusted selling, general and administrative expenses (SG&A), adjusted SG&A as a percentage of revenue, operating earnings (adjusted EBIAT), operating margin (adjusted EBIAT as a percentage of revenue), adjusted net earnings, adjusted net earnings per share, net invested capital, return on invested capital (ROIC), and free cash flow. Adjusted EBIAT, net invested capital, ROIC and free cash flow are further described in the tables below. In calculating these non-IFRS financial measures, management excludes the following items, where applicable: employee stock-based compensation expense, amortization of intangible assets (excluding computer software), restructuring and other charges, net of recoveries (most significantly restructuring charges), the write-down of goodwill, intangible assets and property, plant and equipment, and gains or losses related to the repurchase of shares or debt, net of tax adjustments and significant deferred tax write-offs or recoveries associated with restructuring actions or restructured sites.

We believe the non-IFRS measures we present herein are useful, as they enable investors to evaluate and compare our results from operations and cash resources generated from our business in a more consistent manner (by excluding specific items that we do not consider to be reflective of our ongoing operating results) and provide an analysis of operating results using the same measures our chief operating decision makers use to measure performance. The non-IFRS financial measures that can be reconciled to IFRS measures result largely from management’s determination that the facts and circumstances surrounding the excluded charges or recoveries are not indicative of the ordinary course of our ongoing operation of our business.

Non-IFRS measures do not have any standardized meaning prescribed by IFRS and may not be comparable to similar measures presented by other public companies that use IFRS, or who report under U.S. GAAP and use non-U.S. GAAP measures to describe similar operating metrics. Non-IFRS measures are not measures of performance under IFRS and should not be considered in isolation or as a substitute for any standardized measure under IFRS. The most significant limitation to management’s use of non-IFRS financial measures is that the charges or credits excluded from the non-IFRS measures are nonetheless charges or credits that are recognized under IFRS and that have an economic impact on the company. Management compensates for these limitations primarily by issuing IFRS results to show a complete picture of the company’s performance, and reconciling non-IFRS results back to IFRS results where a comparable IFRS measure exists.

The economic substance of these exclusions and management’s rationale for excluding them from non-IFRS financial measures is provided below:

Employee stock-based compensation expense, which represents the estimated fair value of stock options, restricted share units and performance share units granted to employees, is excluded because grant activities vary significantly from quarter-to-quarter in both quantity and fair value. In addition, excluding this expense allows us to better compare core operating results with those of our competitors who also generally exclude employee stock-based compensation expense from their core operating results, who may have different granting patterns and types of equity awards, and who may use different valuation assumptions than we do, including those competitors who use U.S. GAAP and non-U.S. GAAP measures to present similar metrics.

Amortization charges (excluding computer software) consist of non-cash charges against intangible assets that are impacted by the timing and magnitude of acquired businesses. Amortization of intangible assets varies among our competitors, and we believe that excluding these charges permits a better comparison of core operating results with those of our competitors who also generally exclude amortization charges.

Restructuring and other charges, net of recoveries, include costs relating to employee severance, lease terminations, site closings and consolidations, write-downs of owned property and equipment which are no longer used and are available for sale, reductions in infrastructure and acquisition-related transaction costs. We exclude restructuring and other charges, net of recoveries, because we believe that they are not directly related to ongoing operating results and do not reflect expected future operating expenses after completion of these activities.  We believe these exclusions permit a better comparison of our core operating results with those of our competitors who also generally exclude these charges, net of recoveries, in assessing operating performance.

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Impairment charges, which consist of non-cash charges against goodwill, intangible assets and property, plant and equipment, result primarily when the carrying value of these assets exceeds their recoverable amount. Our competitors may record impairment charges at different times. We believe that excluding these charges permits a better comparison of our core operating results with those of our competitors who also generally exclude these charges in assessing operating performance.

Gains or losses related to the repurchase of shares or debt are excluded, as we believe that these gains or losses do not reflect core operating performance and vary significantly among those of our competitors who also generally exclude these charges or recoveries in assessing operating performance.

Significant deferred tax write-offs or recoveries associated with restructuring actions or restructured sites are excluded, as we believe that these write-offs or recoveries do not reflect core operating performance and vary significantly among those of our competitors who also generally exclude these charges or recoveries in assessing operating performance.

The following table sets forth, for the periods indicated, the various non-IFRS measures discussed above, and a reconciliation of IFRS to non-IFRS measures, where a comparable IFRS measure exists (in millions, except percentages and per share amounts):

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(1)          Management uses non-IFRS operating earnings (adjusted EBIAT) as a measure to assess our operational performance related to our core operations. Non-IFRS adjusted EBIAT is defined as earnings before finance costs (consisting of interest and fees related to our credit facilities and accounts receivable sales program), amortization of intangible assets (excluding computer software) and income taxes.  Non-IFRS adjusted EBIAT also excludes, in periods where such charges have been recorded, employee stock-based compensation expense, restructuring and other charges (net of recoveries), gains or losses related to the repurchase of shares or debt, and impairment charges.

(2)         The adjustments for taxes, as applicable, represent the tax effects on the non-IFRS adjustments and significant deferred tax write-offs or recoveries associated with restructuring actions or restructured sites that management considers not to be reflective of our core operating performance.

(3)         Management uses non-IFRS free cash flow as a measure, in addition to IFRS cash flow from operations, to assess our operational cash flow performance. We believe non-IFRS free cash flow provides another level of transparency to our liquidity. Non-IFRS free cash flow is defined as cash provided by or used in operating activities after the purchase of property, plant and equipment (net of proceeds from the sale of certain surplus equipment and property), advances to a solar supplier for its capital expenditures, and finance costs paid. Non-IFRS free cash flow also includes the cash deposit we received in the third quarter of 2015 upon execution of the agreement to sell our Toronto real property (see note 7 to our September 30, 2015 unaudited interim condensed consolidated financial statements).

(4)         Management uses non-IFRS ROIC as a measure to assess the effectiveness of the invested capital we use to build products or provide services to our customers, by quantifying how well we generate earnings relative to the capital we have invested in our business. Our non-IFRS ROIC measure reflects non-IFRS operating earnings, working capital management and asset utilization. Non-IFRS ROIC is calculated by dividing non-IFRS adjusted EBIAT by average non-IFRS net invested

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capital. Net invested capital (calculated in the table below) is a non-IFRS measure and consists of the following IFRS measures: total assets less cash, accounts payable, accrued and other current liabilities and provisions, and income taxes payable. We use a two-point average to calculate average non-IFRS net invested capital for the quarter and a four-point average to calculate average non-IFRS net invested capital for the nine-month period. There is no comparable measure under IFRS.

The following table sets forth, for the periods indicated, our calculation of non-IFRS ROIC % (in millions, except ROIC %):

(1)         Management uses non-IFRS ROIC as a measure to assess the effectiveness of the invested capital we use to build products or provide services to our customers, by quantifying how well we generate earnings relative to the capital we have invested in our business. Our non-IFRS ROIC measure reflects non-IFRS operating earnings, working capital management and asset utilization. Non-IFRS ROIC is calculated by dividing non-IFRS adjusted EBIAT by average non-IFRS net invested capital. Net invested capital is a non-IFRS measure and consists of the following IFRS measures: total assets less cash, accounts payable, accrued and other current liabilities and provisions, and income taxes payable. We use a two-point average to calculate average non-IFRS net invested capital for the quarter and a four-point average to calculate average non-IFRS net invested capital for the nine-month period. There is no comparable measure under IFRS.

GUIDANCE SUMMARY

(1) Our adjusted EPS (non-IFRS) for the third quarter of 2015 would have been $0.30 per share, within our guidance range, had we excluded an income tax expense of $0.08 per share resulting from taxable foreign exchange impacts (discussed above). See also note 11 to our September 30, 2015 unaudited interim condensed consolidated financial statements.

(2) For the fourth quarter of 2015, we expect a negative $0.06 to $0.12 per share (pre-tax) aggregate impact on net earnings on an IFRS basis for employee stock-based compensation expense and amortization of intangible assets (excluding computer software).

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CELESTICA INC.

CONDENSED CONSOLIDATED BALANCE SHEET

(in millions of U.S. dollars)

(unaudited)

Contingencies (note 13)

The accompanying notes are an integral part of these unaudited interim condensed consolidated financial statements.

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CELESTICA INC.

CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS

(in millions of U.S. dollars, except per share amounts)

(unaudited)

The accompanying notes are an integral part of these unaudited interim condensed consolidated financial statements.

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CELESTICA INC.

CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS)

(in millions of U.S. dollars)

(unaudited)

The accompanying notes are an integral part of these unaudited interim condensed consolidated financial statements.

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CELESTICA INC.

CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN EQUITY

(in millions of U.S. dollars)

(unaudited)