Entegris : to Report Second Quarter Results on Aug. 3, 9am ET

Safe Harbor

This presentation contains forward-looking statements. The words "believe," "expect," "anticipate," "intend," "estimate," "forecast," "project," "should," "may," "will," "would" or the negative thereof

and similar expressions are intended to identify such forward-looking statements. These forward-looking statements may include statements about supply chain matters and inflationary pressures;

future period guidance or projections; the Company's performance relative to its markets, including the drivers of such performance; market and technology trends, including the duration and drivers of any growth trends; the development of new products and the success of their introductions; the focus of the Company's engineering, research and development projects; the Company's ability to execute on our business strategies, including with respect to Company's expansion of its manufacturing presence in Taiwan and in Colorado Springs; the Company's capital allocation strategy, which may be modified at any time for any reason, including share repurchases, dividends, debt repayments and potential acquisitions; the impact of the acquisitions the Company has made and commercial partnerships the Company has established, including the acquisition of CMC Materials, Inc. (now known as CMC Materials LLC) ("CMC Materials"); the closing of any announced divestitures and the termination of strategic partnerships, including the timing thereof; trends relating to the fluctuation of currency exchange rates; future capital and other expenditures, including estimates thereof; the Company's expected tax rate; the impact, financial or otherwise, of any organizational changes; the impact of accounting pronouncements; quantitative and qualitative disclosures about market risk; and

other matters. These forward-looking statements are based on current management expectations and assumptions only as of the date of this Quarterly Report, are not guarantees of future performance and involve substantial risks and uncertainties that are difficult to predict and that could cause actual results to differ materially from the results expressed in, or implied by, these forward-looking statements. These risks and uncertainties include, but are not limited to, weakening of global and/or regional economic conditions, generally or specifically in the semiconductor industry, which could decrease the demand for the Company's products and solutions; the level of, and obligations associated with, the Company's indebtedness, including the debts incurred in connection with the acquisition of CMC Materials; risks related to the acquisition and integration of CMC Materials, including unanticipated difficulties or expenditures relating thereto; the ability to achieve the anticipated synergies and value-creation contemplated by the acquisition of CMC Materials and the diversion of management time on transaction-related matters; raw material shortages, supply and labor constraints, price increases, inflationary pressures and rising interest rates; operational, political and legal risks of the Company's international operations; the Company's dependence on sole source and limited source suppliers; the Company's ability to meet rapid demand shifts; the Company's ability to continue technological innovation and introduce new products to meet customers' rapidly changing

requirements; substantial competition; the Company's concentrated customer base; the Company's ability to identify, complete and integrate acquisitions, joint ventures, divestitures or other similar transactions; the Company's ability to consummate pending transactions on a timely basis or at all and the satisfaction of the conditions precedent to consummation of such pending transactions, including the satisfaction of regulatory conditions on the terms expected, at all or in a timely manner; the Company's ability to effectively implement any organizational changes; the Company's ability to protect and enforce intellectual property rights; the increasing complexity of certain manufacturing processes; changes in government regulations of the countries in which the Company operates, including the imposition of tariffs, export controls and other trade laws and restrictions and changes to national security and international trade policy, especially as they relate to China; fluctuation of currency exchange rates; fluctuations in the market price of the Company's stock; and other risk factors and additional information described in the Company's filings with the Securities and Exchange Commission (the "SEC"), including under the heading "Risk Factors" in Item 1A of the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2022, filed on February 23, 2023, and in the Company's other SEC filings. Except as required under the federal securities laws and the rules and regulations of the SEC, the Company undertakes no obligation to update publicly any

forward-looking statements or information contained herein, which speak as of their respective dates.

This presentation contains references to "Adjusted EBITDA," "Adjusted EBITDA - as a % of Net Sales," "Adjusted Operating Income," "Adjusted Operating Margin," "Adjusted Gross Profit," "Adjusted Gross Margin - as a % of Net Sales," "Adjusted Segment Profit," "Adjusted Segment Profit Margin," "Non-GAAP Operating Expenses," "Non-GAAP Tax Rate," "Non-GAAP Net Income," "Diluted Non- GAAP Earnings per Common Share," "Free Cash Flow" and other measures that are not presented in accordance GAAP. The non-GAAP financial measures should not be considered in isolation or as a substitute for GAAP financial measures but should instead be read in conjunction with the GAAP financial measures. Further information with respect to and reconciliations of such measures to the most directly comparable GAAP measure can be found attached to this presentation. ​

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Summary - Consolidated Statement of Operations (GAAP)

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Summary - Consolidated Statement of Operations (Non-GAAP)1

1. See GAAP to non-GAAP reconciliation tables in the appendix of this presentation.
2. Excludes amortization expense, deal and transaction costs, integration costs, goodwill impairment, restructuring costs and loss on sale of business and held for sale assets.
3. Reflects the tax effect of non-GAAP adjustments and discrete tax items to GAAP taxes.
4. Excludes the items noted in footnotes 2, interest expense, net, Infineum termination fee, loss on extinguishment of debt and modification, and the tax effect of non-GAAP adjustments.

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Microcontamination Control (MC)

2Q23 Highlights

1. See GAAP to non-GAAP reconciliation tables in the appendix of this presentation.

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