Material Event (Form 8-K)

On March 13, 2026, Public Service Company of Colorado, a Colorado corporation ("PSCo"), issued $700,000,000 in aggregate principal amount of 4.15% First Mortgage Bonds, Series No. 45 due March 13, 2029 (the "2029 Bonds") and $600,000,000 in aggregate principal amount of 5.05% First Mortgage Bonds, Series No. 46 due June 15, 2036 (the "2036 Bonds," and, together with the 2029 Bonds, the "Bonds"), pursuant to an Underwriting Agreement among PSCo and BNY Mellon Capital Markets, LLC, CIBC World Markets Corp., J.P. Morgan Securities LLC, Scotia Capital (USA) Inc. and TD Securities (USA) LLC, as representatives of the underwriters named therein. The Bonds are being issued pursuant to the registration statement on Form S-3(File No. 333-278797-02)(the "Registration Statement"). A prospectus supplement relating to the offering and sale of the Bonds was filed with the Securities and Exchange Commission on March 11, 2026. The Bonds will be governed by the Indenture, dated October 1, 1993, by and between PSCo and U.S. Bank Trust Company, National Association, as successor trustee (the "Original Indenture"), as further supplemented by Supplemental Indenture No. 38, dated as of March 1, 2026.

This Current Report on Form 8-Kis being filed to report as exhibits certain documents in connection with that offering and sale for incorporation by reference into the Registration Statement.