Vistra Corp.

6. INCOME TAXES

Vistra files a U.S. federal income tax return that includes the results of its consolidated subsidiaries. Vistra serves as the corporate parent of the Vistra consolidated group. Pursuant to applicable U.S. Department of the Treasury regulations and published guidance of the IRS, corporations that are members of a consolidated group have joint and several liability for the taxes of such group.

Income Tax Expense

The components of our income tax expense are as follows:

We evaluate and update our annual effective income tax rate on an interim basis based on current and forecasted earnings and tax laws. The mix and timing of our actual earnings compared to annual projections, as well as the amount of pre-tax earnings in comparison to the required discrete items, can cause interim effective tax rate fluctuations.

For the three months ended September 30, 2026, the effective tax rate of 23.8% was higher than the U.S. federal statutory rate of 21% due primarily to state income taxes, partially offset by the discrete impact of mark-to-market adjustments accounted for outside of the Company's forecasted annual effective income tax rate. For the nine months ended September 30, 2026, the effective tax rate of 21.1% was higher than the U.S. federal statutory rate of 21% due primarily to state income taxes, partially offset by permanent differences recorded discretely related to tax deductions available for stock-based compensation.

For the three months ended September 30, 2025, the effective tax rate of 23.8% was higher than the U.S. federal statutory rate of 21% due primarily to state income taxes. For the nine months ended September 30, 2025, the effective tax rate of 12.8% was lower than the U.S. federal statutory rate of 21% due primarily to permanent differences recorded discretely related to tax deductions available for stock-based compensation.

Income Taxes Paid

For the nine months ended September 30, 2026 and 2025, we paid federal income taxes ofzero and $11 million, respectively, state income taxes of $41 million and $70 million, respectively, and received state tax refunds of $2 million andzero, respectively.