ON: Material agreement · New financial obligation · Unregistered securities sale · Other company developments

Item 1.01. Entry into a Material Definitive Agreement. On May 11, 2026, ON Semiconductor Corporation (the “ Company ”) completed its previously announced private unregistered offering of $1.5 billion aggregate principal amount of its 0% Convertible Senior Notes due 2031 (the “ Notes ”), which amount includes the full exercise of the initial purchasers’ option to purchase $200 million aggregate principal amount of additional Notes. Indenture The Notes were issued under an Indenture, dated as of May 11, 2026 (the “ Indenture ”), by and among the Company, the Guarantors (as defined below) and Computershare Trust Company, National Association, as trustee (the “ Trustee ”). The Indenture provides, among other things, that the Notes will mature on May 1, 2031, unless earlier repurchased or redeemed by the Company or converted pursuant to their terms. The Notes will not bear regular interest, and the principal amount of the Notes will not accrete. The Notes are fully and unconditionally guaranteed, on a joint and several basis, by each of the Company’s U.S. subsidiaries (the “ Guarantors ”) that is a borrower or guarantor under the Credit Agreement, dated as of June 22, 2023 (as amended, extended, renewed, restated, supplemented or otherwise modified from time to time, the “ Credit Agreement ”), among the Company, as borrower, the several lenders party thereto and JPMorgan Chase Bank, N.A., as administrative agent. In the future, the Notes will be fully and unconditionally guaranteed by each of the Company’s U.S. subsidiaries that becomes a borrower or guarantees any indebtedness under the Credit Agreement. The Company received net proceeds from the offering of the Notes of approximately $1,472.9 million, after deducting the initial purchasers’ discounts and after deducting of