Material Event (Form 8-K)

On September 21, 2026, Dominion Energy South Carolina, Inc. (the Company) entered into an underwriting agreement (the Underwriting Agreement) with BNP Paribas Securities Corp. and Scotia Capital (USA) Inc., as Representatives for the underwriters named in the Underwriting Agreement, for the sale of $300,000,000 aggregate principal amount of the Company's 2026 Series A 6.15% First Mortgage Bonds due 2056 (the Bonds). The Bonds are First Mortgage Bonds that were registered by the Company under Rule 415 under the Securities Act of 1933, as amended, pursuant to a registration statement on Form S-3, which became effective on February 23, 2024 (File No. 333-277322-01). A copy of the Underwriting Agreement, including exhibits thereto, is filed as Exhibit 1.1 to this Form 8-K.

The Bonds will be issued under the Company's April 1, 1993 Indenture.