Cover and table of contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2025

Or

For the transition period from to

(Commission File Number) 001-39317

ON SEMICONDUCTOR CORPORATION

(Exact name of registrant as specified in its charter)

5701 N. Pima Road

Scottsdale, AZ 85250

(602) 244-6600

(Address, zip code and telephone number, including area code, of principal executive offices)

Securities Registered Pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☒ No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐ No ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

If emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. Yes ☒ No ☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant was $23,198,209,519 as of July 4, 2025, based on the closing sales price of such stock on the Nasdaq Global Select Market. Shares held by executive officers, directors and persons owning directly or indirectly more than 10% of the outstanding common stock (as applicable) have been excluded from the preceding number because such persons may be deemed to be affiliates of the registrant.

The number of shares of the registrant's common stock outstanding at February 4, 2026 was 394,020,530.

Documents Incorporated by Reference

Portions of the registrant's Definitive Proxy Statement relating to its 2026 Annual Meeting of Stockholders, which is expected to be filed pursuant to Regulation 14A within 120 days after the registrant's fiscal year ended December 31, 2025, are incorporated by reference into Part III of this Form 10-K where indicated.

ON SEMICONDUCTOR CORPORATION

FORM 10-K

TABLE OF CONTENTS

(See the glossary immediately following this table of contents for definitions of certain abbreviated terms)

ON SEMICONDUCTOR CORPORATION

FORM 10-K

GLOSSARY OF SELECTED ABBREVIATED TERMS*

• Terms used, but not defined, within the body of the Form 10-K are defined in this Glossary.

PART I