Exhibit 99.1

onsemi First Quarter 2024 Results Exceed Expectations

Increased free cash flow approximately 3x year-over-year

SCOTTSDALE, Ariz, – Apr 29, 2024 – onsemi (the “Company”) (Nasdaq: ON) today announced results for the first quarter of 2024 with the following highlights:

“The structural changes we have made to the business over the last three years have enabled us to sustain our gross margin despite challenging market conditions,” said Hassane El-Khoury, president and chief executive officer of onsemi. “In the current environment, we remain focused on execution while investing for our long-term growth. As power continues to play a critical role in the world’s increasing energy demands, efficiency is paramount, and we are positioned to continue to gain share with our portfolio of industry-leading power and sensing technologies.”

Selected financial results for the quarter are shown below with comparable periods (unaudited):

Revenue Summary

(in millions)

(Unaudited)

⁽¹⁾ During the first quarter of 2024, the Company reorganized certain reporting units and its segment reporting structure. As a result of the reorganization of divisions within PSG and AMG, the prior-period amounts have been reclassified to conform to current-period presentation.

SECOND QUARTER 2024 OUTLOOK

The following table outlines onsemi’s projected second quarter of 2024 GAAP and non-GAAP outlook.

2

TELECONFERENCE

onsemi will host a conference call for the financial community at 9 a.m. Eastern Time (ET) on April 29,2024 to discuss this announcement and onsemi’s 2024 first quarter results. The Company will also provide a real-time audio webcast of the teleconference on the Investor Relations page of its website at http://www.onsemi.com. The webcast replay will be available at this site approximately one hour following the live broadcast and will continue to be available for approximately 30 days following the conference call. Investors and interested parties can also access the conference call by pre-registering here.

3

About onsemi

onsemi (Nasdaq: ON) is driving disruptive innovations to help build a better future. With a focus on automotive and industrial end-markets, the company is accelerating change in megatrends such as vehicle electrification and safety, sustainable energy grids, industrial automation, and 5G and cloud infrastructure. onsemi offers a highly differentiated and innovative product portfolio, delivering intelligent power and sensing technologies that solve the world’s most complex challenges and leads the way to creating a safer, cleaner, and smarter world. onsemi is recognized as a Fortune 500^® company and included in the Nasdaq-100 Index^® and S&P 500^® index. Learn more about onsemi at www.onsemi.com.

# # #

onsemi and the onsemi logo are trademarks of Semiconductor Components Industries, LLC. All other brand and product names appearing in this document are registered trademarks or trademarks of their respective holders. Although the Company references its website in this news release, information on the website is not to be incorporated herein.

This document includes “forward-looking statements,” as that term is defined in Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. All statements, other than statements of historical facts, included or incorporated in this document could be deemed forward-looking statements, particularly statements about the future financial performance of onsemi, including financial guidance for the second quarter of 2024. Forward-looking statements are often characterized by the use of words such as “believes,” “estimates,” “expects,” “projects,” “may,” “will,” “intends,” “plans,” “anticipates,” “should” or similar expressions or by discussions of strategy, plans or intentions. All forward-looking statements in this document are made based on our current expectations, forecasts, estimates and assumptions and involve risks, uncertainties and other factors that could cause results or events to differ materially from those expressed in the forward-looking statements. Certain factors that could affect our future results or events are described under Part I, Item 1A “Risk Factors” in the 2023 Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on February 5, 2024 (the “2023 Form 10-K”) and from time to time in our other SEC reports. Readers are cautioned not to place undue reliance on forward-looking statements. We assume no obligation to update such information, which speaks only as of the date made, except as may be required by law. Investing in our securities involves a high degree of risk and uncertainty, and you should carefully consider the trends, risks and uncertainties described in this document, our 2023 Form 10-K and other reports filed with or furnished to the SEC before making any investment decision with respect to our securities. If any of these trends, risks or uncertainties actually occurs or continues, our business, financial condition or operating results could be materially adversely affected, the trading prices of our securities could decline, and you could lose all or part of your investment. All forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by this cautionary statement.

4

ON SEMICONDUCTOR CORPORATION

UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS

(in millions, except per share data)

5

ON SEMICONDUCTOR CORPORATION

UNAUDITED CONSOLIDATED BALANCE SHEETS

(in millions)

6

ON SEMICONDUCTOR CORPORATION

UNAUDITED CONSOLIDATED STATEMENTS OF CASH FLOWS

(in millions)

7

ON SEMICONDUCTOR CORPORATION

RECONCILIATION OF GAAP VERSUS NON-GAAP DISCLOSURES

(in millions, except per share and percentage data)

8

ON SEMICONDUCTOR CORPORATION

RECONCILIATION OF GAAP VERSUS NON-GAAP DISCLOSURES (Continued)

(in millions, except per share and percentage data)

Certain of the amounts in the above tables may not total due to rounding of individual amounts.

Total share-based compensation related to restricted stock units, stock grant awards and the employee stock purchase plan is included below:

9

ON SEMICONDUCTOR CORPORATION

RECONCILIATION OF GAAP VERSUS NON-GAAP DISCLOSURES (Continued)

(in millions, except per share and percentage data)

SUPPLEMENTAL FINANCIAL DATA

10

NON-GAAP MEASURES

To supplement the consolidated financial results prepared in accordance with GAAP, onsemi uses certain non-GAAP measures, which are adjusted from the most directly comparable GAAP measures to exclude items related to the amortization of acquisition-related intangibles, expensing of appraised inventory fair market value step-up, inventory valuation adjustments, in-process research and development expenses, restructuring, asset impairments and other, net, goodwill impairment charges, gains and losses on debt prepayment, non-cash interest expense, actuarial (gains) losses on pension plans and other pension benefits, third party acquisition and divestiture-related costs, tax impact of these items and certain other non-recurring items, as necessary. Management does not consider the effects of these items in evaluating the core operational activities of onsemi. Management uses these non-GAAP measures internally to make strategic decisions, forecast future results and evaluate onsemi’s current performance. In addition, the Company believes that most analysts covering onsemi use the non-GAAP measures to evaluate onsemi’s performance. Given management’s and other relevant parties’ use of these non-GAAP measures, onsemi believes these measures are important to investors in understanding onsemi’s current and future operating results as seen through the eyes of management. In addition, management believes these non-GAAP measures are useful to investors in enabling them to better assess changes in onsemi’s core business across different time periods. These non-GAAP measures are not prepared in accordance with, and should not be considered alternatives or necessarily superior to, GAAP financial data and may be different from non-GAAP measures used by other companies. Because non-GAAP financial measures are not standardized, it may not be possible to compare these financial measures with other companies’ non-GAAP financial measures, even if they have similar names.

Non-GAAP Revenue

The use of non-GAAP revenue allows management to evaluate, among other things, the revenue from the Company’s core businesses and trends across different reporting periods on a consistent basis, independent of special items. In addition, non- GAAP revenue is an important component of management’s internal performance measurement and incentive and reward process as it is used to assess the current and historical financial results of the business and for strategic decision making, preparing budgets, obtaining targets and forecasting future results. Management presents this non-GAAP financial measure to enable investors and analysts to evaluate the Company’s revenue generation performance relative to the direct costs of operations of onsemi’s core businesses.

Non-GAAP Gross Profit and Gross Margin

The use of non-GAAP gross profit and gross margin allows management to evaluate, among other things, the gross margin and gross profit of the Company’s core businesses and trends across different reporting periods on a consistent basis, independent of non-cash items including, generally speaking, expensing of appraised inventory fair market value step-up, impact of business wind down and non-recurring facility costs. In addition, it is an important component of management’s internal performance measurement and incentive and reward process as it is used to assess the current and historical financial results of the business and for strategic decision making, preparing budgets, obtaining targets and forecasting future results. Management presents this non-GAAP financial measure to enable investors and analysts to evaluate our revenue generation performance relative to the direct costs of revenue of onsemi’s core businesses.

Non-GAAP Operating Income and Operating Margin

The use of non-GAAP operating income and operating margin allows management to evaluate, among other things, the operating margin and operating income of the Company’s core businesses and trends across different reporting periods on a consistent basis, independent of non-cash items including, generally speaking, expensing of appraised inventory fair market value step-up, impact of business wind down, non-recurring facility costs, amortization and impairments of intangible assets, third party acquisition and divestiture-related costs, restructuring charges and certain other special items as necessary. In addition, it is an important component of management’s internal performance measurement and incentive and reward process as it is used to assess the current and historical financial results of the business and for strategic decision making, preparing budgets, obtaining targets and forecasting future results. Management presents this non-GAAP financial measure to enable investors and analysts to evaluate the Company’s revenue generation performance relative to the direct costs of operations of onsemi’s core businesses.

11

NON-GAAP MEASURES (Continued)

Non-GAAP Net Income Attributable to ON Semiconductor Corporation and Non-GAAP Diluted Earnings Per Share

The use of non-GAAP net income attributable to onsemi and non-GAAP diluted earnings per share allows management to evaluate the operating results of onsemi’s core businesses and trends across different reporting periods on a consistent basis, independent of non-cash items including, generally, the amortization and impairments of intangible assets, expensing of appraised inventory fair market value step-up, impact of business wind down, non-recurring facility costs, restructuring, gains and losses on debt prepayment, actuarial (gains) losses on pension plans and other pension benefits, third party acquisition and divestiture-related costs, discrete tax items and other non-GAAP tax adjustments and certain other special items, as necessary. In addition, these items are important components of management’s internal performance measurement and incentive and reward process, as they are used to assess the current and historical financial results of the business and for strategic decision making, preparing budgets, setting targets and forecasting future results. For our non-GAAP reporting, we are utilizing a projected and normalized non-GAAP effective tax rate of 16%. We calculate this non-GAAP effective tax rate on an annual basis. We expect to use this normalized non-GAAP effective tax rate of 16% through 2025, however, we may update this non-GAAP effective tax rate at any time for a variety of reasons, including, but not limited to, the rapidly evolving global tax environment, significant changes in our geographic earnings mix or changes to our strategy or business operations. Management presents these non-GAAP financial measures to enable investors and analysts to understand the results of operations of onsemi’s core businesses and, to the extent comparable, to compare our results of operations on a more consistent basis against those of other companies in our industry.

Free Cash Flow

The use of free cash flow allows management to evaluate, among other things, the ability of the Company to make interest or principal payments on its debt. Free cash flow is defined as the difference between cash flow from operating activities and capital expenditures disclosed under investing activities in the consolidated statement of cash flows. Free cash flow is not an alternative to cash flow from operating activities as a measure of liquidity. It is an important component of management’s internal performance measurement and incentive and reward process as it is used to assess the current and historical financial results of the business and for strategic decision making, preparing budgets, obtaining targets and forecasting future results. Management presents this non-GAAP financial measure to enable investors and analysts to evaluate our revenue generation performance relative to the direct costs of operations of onsemi’s core businesses.

Non-GAAP Diluted Share Count

The use of non-GAAP diluted share count allows management to evaluate, among other things, the potential dilution due to the outstanding restricted stock units excluding the dilution from the convertible notes that is covered by hedging activity up to a certain threshold. In periods when the quarterly average stock price per share exceeds $52.97 for the 0% Notes and $103.87 for the 0.50% Notes, the non-GAAP diluted share count includes the anti-dilutive impact of the Company’s hedge transactions issued concurrently with the 0% Notes and the 0.50% Notes, respectively. At an average stock price per share between $52.97 and $74.34 for the 0% Notes and $103.87 and $156.78 for the 0.50% Notes, the hedging activity offsets the potentially dilutive effect of the 0% Notes and the 0.50% Notes, respectively. In periods when the quarterly average stock price exceeds $74.34 for the 0% Notes and $156.78 for the 0.50% Notes, the dilutive impact of the warrants issued concurrently with such notes are included in the diluted shares outstanding.

12