UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

☐	Preliminary Proxy Statement

☐	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☐	Definitive Proxy Statement

☒	Definitive Additional Materials

☐	Soliciting Material under §240.14a-12

ON Semiconductor Corporation

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant) Payment of Filing Fee (Check all boxes that apply):

☒	No fee required.

☐	Fee paid previously with preliminary materials.

☐	Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11

Your Vote Counts! Smartphone users Point your camera here and vote without entering a control number For complete information and to vote, visit www.ProxyVote.com Control # V61895-P26377 ON SEMICONDUCTOR CORPORATION 2025 Annual Meeting Vote by May 14, 2025 11:59 PM ET ON SEMICONDUCTOR CORPORATION 5701 NORTH PIMA ROAD SCOTTSDALE, AZ 85250 You invested in ON SEMICONDUCTOR CORPORATION and it’s time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy materials for the stockholder meeting to be held on May 15, 2025. Get informed before you vote View the Notice and Proxy Statement and Annual Report online OR you can receive a free paper or email copy of the material(s) by requesting prior to May 1, 2025. These materials contain important information. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy. Vote in Person at the Meeting* May 15, 2025 8:00 a.m. local time ON SEMICONDUCTOR CORPORATION Principal Executive Offices 5701 North Pima Road Scottsdale, AZ 85250 *You may obtain directions to be able to attend the Annual Meeting and vote in person by visiting onsemi’s website at www.onsemi.com. Many stockholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares.

Vote at www.ProxyVote.com THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters. Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Delivery Settings”. V61896-P26377 1. To elect eight directors nominated by our Board of Directors. Nominees: 1a. Alan Campbell For 1b. Susan K. Carter For 1c. Thomas L. Deitrich For 1d. Hassane El-Khoury For 1e. Bruce E. Kiddoo For 1f. Paul A. Mascarenas For 1g. Gregory L. Waters For 1h. Christine Y. Yan For 2. Advisory vote to approve the compensation of our named executive officers (Say-on-Pay). For 3. Ratification of the selection of PricewaterhouseCoopers LLP as our independent registered accounting firm for the year ending December 31, 2025. For NOTE: To transact such other business as may properly come before the meeting and any adjournment or postponement of the meeting. Voting Items Board Recommends