Non-IFRS Supplementary Information

In addition to disclosing detailed operating results in accordance with IFRS, Celestica provides supplementary non-IFRS financial measures to consider in evaluating the company’s operating performance. Management uses adjusted net earnings and other non-IFRS financial 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 financial measures to assess management's 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 below.

About Celestica

Celestica enables the world's best brands. Through our recognized customer-centric approach, we partner with leading companies in Aerospace and Defense, Communications, Enterprise, HealthTech, Industrial, and Capital Equipment to deliver solutions for their most complex challenges. As a leader in design, manufacturing, hardware platform and supply chain solutions, Celestica brings global expertise and insight at every stage of product development - from the drawing board to full-scale production and after-market services. With talented teams across North America, Europe and Asia, we imagine, develop and deliver a better future with our customers. For more information on Celestica, visit www.celestica.com. Our securities filings can be accessed at  www.sedar.com and www.sec.gov.

Cautionary Note Regarding Forward-looking Statements

This press release contains forward-looking statements, including, without limitation, those related to: our anticipated financial and/or operational results and outlook, including statements made, and guidance and outlook provided, under the headings "Second Quarter of 2023 (Q2 2023) Guidance" and "2023 Outlook Update"; our credit risk; our liquidity; anticipated charges and expenses, including restructuring charges; the potential impact of tax and litigation outcomes; mandatory prepayments under our credit facility; interest rates; and our expectations with respect to insurance recoveries for tangible losses in connection with a recent fire at our Batam facility in Indonesia (Batam Fire). 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,” "target," "outlook," "goal," "guidance", “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 forward looking statements attributable to Celestica, we claim the protection of the safe harbor for forward-looking statements contained in the U.S. Private Securities Litigation Reform Act of 1995, where applicable, and for forward-looking information under applicable Canadian securities laws. This press release also contains forward-looking statements related to Onex’ intentions with respect to Celestica’s securities. All forward-looking statements herein attributable to Onex are derived from the Statement on Schedule 13D/A filed by Gerald W. Schwartz with the U.S. Securities and Exchange Commission on March 14, 2023. We are not aware of Onex’s material assumptions underlying such statements or what Onex believes to be the material risks of such statements ultimately proving to be incorrect. Accordingly, we do not assume any responsibility or liability for the verification, accuracy or completeness of such information nor for updating or withdrawing such information should circumstance change in the future. There can be no assurance that Onex will convert any or all of its holdings of MVS into SVS or sell any holdings of Celestica securities.

Forward-looking statements are provided to assist 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 those expressed or implied in such forward-looking statements, including, among others, risks related to: customer and segment concentration; challenges of replacing revenue from completed, lost or non-renewed programs or customer disengagements; managing our business during uncertain market, political and economic conditions, including among others, global inflation and/or recession, and geopolitical and other risks associated with our international operations, including military actions, protectionism and reactive countermeasures, economic or other sanctions or trade barriers, including in relation to the Russia/Ukraine conflict; managing changes in customer demand; our customers' ability to compete and succeed using our products and services; delays in the delivery and availability of components, services and/or materials, as well as their costs and quality; our inventory levels and practices; the cyclical and volatile nature of our semiconductor business; changes in our mix of customers and/or the types of products or services we provide, including negative impacts of higher concentrations of lower margin programs; price, margin pressures, and other competitive factors and adverse market conditions affecting, and the highly competitive nature of, the electronic manufacturing services (EMS) and original design manufacturer (ODM) industries in general and our segments in particular (including the risk that anticipated market conditions do not materialize); challenges associated with new customers or programs, or the provision of new services; interest rate fluctuations; rising commodity, materials and component costs as well as rising labor costs and changing labor conditions; changes in U.S. policies or legislation; customer relationships with emerging companies; recruiting or retaining skilled talent; our ability to adequately protect intellectual property and confidential information; the variability of revenue and operating results; unanticipated disruptions to our cash flows; deterioration in financial markets or the macro-economic environment, including as a result of global inflation and/or recession; maintaining sufficient financial resources to fund currently anticipated financial actions and obligations and to pursue desirable business opportunities; the expansion or consolidation of our operations; the inability to maintain adequate utilization of our workforce; integrating and achieving the anticipated benefits from acquisitions and "operate-in-place" arrangements; execution and/or quality issues (including our ability to successfully resolve these challenges); non-performance by counterparties; negative impacts on our business resulting from any significant uses of cash, securities issuances, and/or additional increases in third-party indebtedness (including as a result of an inability to sell desired amounts under our uncommitted accounts receivable sales program or supplier financing programs); disruptions to our operations, or those of our customers, component suppliers and/or logistics partners, including as a result of events outside of our control (including those described in "External Factors that May Impact our Business" in Item 5 of our 2022 Annual Report on Form 20-F); defects or deficiencies in our products, services or designs; volatility in the commercial aerospace industry; compliance with customer-driven policies and standards, and third-party certification requirements; negative impacts on our business resulting from our third-party indebtedness; the scope, duration and impact of materials constraints; coronavirus disease 2019 (COVID-19) mutations or resurgences; declines in U.S. and other government budgets, changes in government spending or budgetary priorities, or delays in contract awards; failure of the U.S. federal government to manage its fiscal matters or to raise or further suspend the debt ceiling, and changes in the amount of U.S. federal debt; the military conflict between Russia and Ukraine; changes to our operating model; foreign currency volatility; our global operations and supply chain; competitive bid selection processes; our dependence on industries affected by rapid technological change; rapidly evolving and changing technologies, and changes in our customers' business or outsourcing strategies; increasing taxes (including as a result of global tax reform), tax audits, and challenges of defending our tax positions; obtaining, renewing or meeting the conditions of tax incentives and credits; the management of our information technology systems, and the fact that while we have not been materially impacted by computer viruses, malware, ransomware, hacking incidents or outages, we have been (and may in the future be) the target of such events; the impact of our restructuring actions and/or productivity initiatives, including a failure to achieve anticipated benefits therefrom; the incurrence of future restructuring charges, impairment charges, other unrecovered write-downs of assets (including inventory) or operating losses; the inability to prevent or detect all errors or fraud; compliance with applicable laws and regulations; our pension and other benefit plan obligations; changes in accounting judgments, estimates and assumptions; our ability to maintain compliance with applicable credit facility covenants; the discontinuation of LIBOR; our entry into a total return swap agreement; our ability to refinance our indebtedness from time to time; our credit rating; the interest and actions of our controlling shareholder; our eligibility for foreign private issuer status; activist shareholders; current or future litigation, governmental actions, and/or changes in legislation or accounting standards; volatility in our SVS price; the impermissibility of SVS repurchases, or a determination not to repurchase SVS, under any normal course issuer bid (NCIB); potential unenforceability of judgments; negative publicity; the impact of climate change; and our ability to achieve our environmental, social and governance targets and goals, including with respect to climate change and greenhouse gas emissions reduction. 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 most recent Management's Discussion and Analysis of Financial Condition and Results of Operations, our 2022 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 as applicable, the Canadian Securities Administrators. Risks also include that Onex does not convert its then-held Celestica MVS into SVS in approximately 6 months, or at all.