Vistra files 8-K: entry into a material agreement, creation of a material debt / off-balance-sheet obligation

Item 1.01. Entry into a Material Definitive Agreement.

On September 30, 2026, Vistra Operations Company LLC (“Borrower”), an indirect, wholly owned subsidiary of Vistra Corp. (the “Company”), entered into an amendment (the “Credit Agreement Amendment”) to that certain credit agreement (as amended, including by the Credit Agreement Amendment, the “Commodity-Linked Credit Agreement”), dated as of February 4, 2022, by and among Borrower, the lenders party thereto and

Citibank, N.A., as administrative agent.

Pursuant to the Credit Agreement Amendment, effective as of September 30, 2026, the Credit Agreement was amended to, among other things, (i) extend the Revolving Credit

Maturity Date (as defined in the Commodity-Linked Credit Agreement) from September 30, 2026 to September 29, 2027 and (ii) make certain other amendments consistent with the terms of the Borrower’s Corporate Credit Agreement (as defined in the

Commodity-Linked Credit Agreement).

A copy of the Credit Agreement Amendment is filed as Exhibit 10.1 to this Current Report on Form 8-K (this “Current Report”) and is incorporated herein by reference. The foregoing summary of the Credit Agreement Amendment does not purport to be complete and is subject to, and qualified in its entirety by, the full text of the Credit Agreement Amendment.

Item 2.03. Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

The information contained in Item 1.01 of this Current Report concerning the Company’s direct financial obligations under the Credit Agreement Amendment is incorporated by reference herein.