Vistra Corp.

Results of Operations

Net income decreased $1.185 billion to $652 million for the three months ended September 30, 2025 compared to the three months ended September 30, 2024. Net income decreased $1.611 billion to $711 million for the nine months ended September 30, 2025 compared to the nine months ended September 30, 2024. For additional information see the following discussion of our results of operations.

EBITDA and Adjusted EBITDA

In analyzing and planning for our business, we supplement our use of GAAP financial measures with non-GAAP financial measures, including EBITDA and Adjusted EBITDA as performance measures. These non-GAAP financial measures reflect an additional way of viewing aspects of our business that, when viewed (i) with our GAAP results and (ii) the accompanying reconciliations to corresponding GAAP financial measures may provide a more complete understanding of factors and trends affecting our business. Because EBITDA and Adjusted EBITDA are financial measures that management uses to allocate resources, determine our ability to fund capital expenditures, assess performance against our peers, and evaluate overall financial performance, we believe they provide useful information for investors.

These non-GAAP financial measures should not be relied upon to the exclusion of GAAP financial measures and are, by definition, an incomplete understanding of Vistra and must be considered in conjunction with GAAP measures. In addition, non-GAAP financial measures are not standardized; therefore, it may not be possible to compare these financial measures with other companies' non-GAAP financial measures having the same or similar names. We strongly encourage investors to review the condensed consolidated financial statements and publicly filed reports in their entirety and not rely on any single financial measure.

When EBITDA or Adjusted EBITDA is discussed in reference to performance on a consolidated basis, the most directly comparable GAAP financial measure to EBITDA and Adjusted EBITDA is Net income (loss).

Vistra Consolidated Financial Results — Three Months Ended September 30, 2025 Compared to the Three Months Ended September 30, 2024

The following table presents Net income (loss), EBITDA and Adjusted EBITDA for the three months ended September 30, 2025:

(a)Includes $10 million of unrealized mark-to-market net losses on interest rate swaps.

(b)Includes nuclear fuel amortization of $35 million and $94 million, respectively, in the Texas and East segments.

(c)Represents net of all NDT (income) loss of the PJM nuclear facilities and all ARO and environmental remediation expenses.

The following table presents Net income (loss), EBITDA and Adjusted EBITDA for the three months ended September 30, 2024:

(a)Includes $84 million of unrealized mark-to-market net losses on interest rate swaps.

(b)Includes nuclear fuel amortization of $28 million and $95 million, respectively, in the Texas and East segments.

(c)Represents net of all NDT (income) loss, ARO accretion expense for operating assets, and ARO remeasurement impacts for operating assets.

GAAP Net income decreased $1.185 billion to $652 million for the three months ended September 30, 2025 compared to the three months ended September 30, 2024. The primary drivers for the decrease in GAAP Net income include:

Unfavorable impacts:

•A decrease of $1.671 billion in unrealized mark-to-market gains on commodity derivative positions. See further information on our derivative results in Energy-Related Commodity Contracts and Mark-to-Market Activities below.

•An increase of $39 million in operating costs due primarily to increased plant maintenance and outage expenses.

•An increase of $33 million in selling, general and administrative expenses due primarily to stock-based incentive compensation expense and technology and consulting costs.

•A decrease of $31 million in other income, net due primarily to a decrease in insurance income.

•An increase of $5 million in impairment of long-lived assets related to certain development projects in the three months ended September 30, 2025.

Favorable impacts:

•An increase of $191 million in realized revenue net fuel due primarily to nuclear PTC revenue of $145 million recognized in the three months ended September 30, 2025 and higher realized energy and capacity prices partially offset by lower energy production due to the Martin Lake Incident and higher retail supply costs outside of ERCOT.

•A decrease in interest expense due primarily to a decrease in unrealized mark-to-market net losses on interest rate swaps.

•A decrease in income tax expense due to lower pre-tax income.

The following table presents the operational performance of our retail and generation segments:

(a)Reflects cooling degree or heating degree days based on Weather Services International (WSI) data. A degree day compares the average of the hourly outdoor temperatures during each day to a 65° Fahrenheit base temperature. Retail amounts represent weather data for the Dallas-Fort Worth area.

(a) Reflects the average around-the-clock settled prices for the periods presented and does not necessarily reflect prices we realized.

(b)Reflects the average around-the-clock settled prices for the periods presented and does not reflect costs incurred by us.

Adjusted EBITDA for the three months ended September 30, 2025 compared to the three months ended September 30, 2024 increased by $137 million. The primary drivers for the increase include:

(a) See Energy-Related Commodity Contracts and Mark-to-Market Activities below for analysis of hedging strategy.

Vistra Consolidated Financial Results — Nine Months Ended September 30, 2025 Compared to the Nine Months Ended September 30, 2024

The following table presents Net income (loss), EBITDA and Adjusted EBITDA for the nine months ended September 30, 2025:

(a)Includes $84 million of unrealized mark-to-market net losses on interest rate swaps.

(b)Includes nuclear fuel amortization of $96 million and $270 million, respectively, in the Texas and East segments.

(c)Includes involuntary conversion gain recognized from Martin Lake Incident property damage insurance in the Texas segment and revenues from Moss Landing Incident business interruption proceeds in the Asset Closure segment.

(d)Represents net of all NDT (income) loss of the PJM nuclear facilities and all ARO and environmental remediation expenses.

(e)Includes the final application of bill credits to large commercial and industrial customers that curtailed their usage during Winter Storm Uri in the Retail segment.

The following table presents Net income (loss), EBITDA and Adjusted EBITDA for the nine months ended September 30, 2024:

(a)Includes $26 million of unrealized mark-to-market net losses on interest rate swaps.

(b)Includes nuclear fuel amortization of $80 million and $189 million, respectively, in the Texas and East segments.

(c)Includes $10 million gain recognized on the repurchase of TRA Rights.

(d)Represents net of all NDT (income) loss, ARO accretion expense for operating assets, and ARO remeasurement impacts for operating assets.

GAAP Net income decreased $1.611 billion to $711 million for the nine months ended September 30, 2025 compared to the nine months ended September 30, 2024. The primary drivers for the decrease in GAAP Net income include:

Unfavorable impacts:

•An increase of $2.092 billion in unrealized mark-to-market losses on commodity derivative positions. See further information on our derivative results in Energy-Related Commodity Contracts and Mark-to-Market Activities below.

•An increase of $77 million in operating costs due to the Moss Landing Incident, net of expected insurance recoveries.

•An increase of $73 million in impairment of long-lived assets related to certain development projects in the nine months ended September 30, 2025.

•An increase in interest expense due primarily to higher debt balances and an increase in unrealized mark-to-market net losses on interest rate swaps

Favorable impacts:

•Inclusion of nine months of Energy Harbor revenues net of expenses in the East and Retail segments for 2025 compared to seven months in 2024

•An increase in realized revenue net fuel due to higher realized energy and capacity prices in East, nuclear PTC revenue and higher retail margins driven by favorable power supply costs and customer count growth, partially offset by lower energy production due to the Martin Lake Incident.

•An increase in insurance income due primarily to $80 million of involuntary conversion gains on property damage insurance from the Martin Lake Incident and $22 million of business interruption revenue from the Moss Landing Incident recognized in the three months ended June 30, 2025 partially offset by $21 million of insurance income recognized in 2024.

•An increase of $27 million in NDT income due to realized and unrealized gains on equity securities.

•A decrease in income tax expense due to lower pre-tax income and a lower effective tax rate.

The following table presents the operational performance of our retail and generation segments:

(a)Reflects cooling degree or heating degree days based on Weather Services International (WSI) data. A degree day compares the average of the hourly outdoor temperatures during each day to a 65° Fahrenheit base temperature. Retail amounts represent weather data for the Dallas-Fort Worth area.

(a) Reflects the average around-the-clock settled prices for the periods presented and does not necessarily reflect prices we realized.

(b)Reflects the average around-the-clock settled prices for the periods presented and does not reflect costs incurred by us.

Adjusted EBITDA for the nine months ended September 30, 2025 compared to the nine months ended September 30, 2024 increased by $507 million. The primary drivers for the increase include:

(a) Includes amounts associated with operations acquired in the Energy Harbor Merger beginning March 1, 2024.

(b)See Energy-Related Commodity Contracts and Mark-to-Market Activities below for analysis of hedging strategy.

Asset Closure Segment — Three and Nine Months Ended September 30, 2025 Compared to Three and Nine Months Ended September 30, 2024

GAAP results for the nine months ended months ended September 2025 are unfavorable compared to the nine months ended months ended September 2024 primarily due to costs associated with the Moss Landing Incident net of insurance receivables. Adjusted EBITDA for the nine months ended months ended September 2025 is unfavorable compared to the nine months ended months ended September 2024 primarily due to a decrease in revenue due to the Moss Landing Incident. See Note 1 to the Financial Statements for additional information.

Energy-Related Commodity Contracts and Mark-to-Market Activities

As we entered the 2024 and 2025 calendar years, we had substantially all of our expected generation volumes hedged. This strategic hedging allowed us to lock in margins that were higher than what we would have realized if we had not hedged. These margins also exceeded those from hedging activities for the nine months ended September 30, 2024, contributing to the increase in realized revenue net of fuel in our generation segments, along with the addition of Energy Harbor.

The changes in unrealized gains and losses on hedging activities are driven by forward power sales. When power prices increase or decrease compared to what our generation segments have sold forward, the generation segments recognize unrealized losses or gains, respectively. Conversely, the retail segment, which procures power from the generation segments to meet future load obligations, experiences an inverse effect on unrealized mark-to-market valuations compared to the generation segments.

During the three and nine months ended September 30, 2025 and 2024, forward power price curves decreased relative to our hedged positions resulting in unrealized gains in the Texas and West segments.

During the three and nine months ended September 30, 2025, forward power price curves in the East segment increased relative to our hedged positions resulting in unrealized losses compared to a decrease in power price curves resulting in unrealized gains in the three and nine months ended September 30, 2024.

These unrealized gains and losses in the Texas, East and West generation segments across these comparative periods were partially offset by unrealized gains and losses in the Retail segment across the same periods.

The table below summarizes the changes in commodity contract assets and liabilities for the nine months ended September 30, 2025 and 2024.

(a)Represents reversals of previously recognized unrealized gains and losses upon settlement/termination (offsets realized gains/(losses) recognized in the settlement period). Excludes changes in fair value in the month the position settled as well as amounts related to positions entered into, and settled, in the same month.

(b)Represents unrealized net gains/(losses) recognized, reflecting the effect of changes in fair value. Excludes changes in fair value in the month the position settled as well as amounts related to positions entered into, and settled, in the same month.

(c)Includes fair value of commodity contracts acquired in the Energy Harbor Merger (see Note 2 to the Financial Statements for additional information).

(d)Primarily represents changes in fair value of positions due to receipt or payment of cash not reflected in unrealized gains or losses. Amounts are generally related to premiums related to options purchased or sold as well as certain margin deposits classified as settlement for certain transactions executed on the CME.

The following maturity table presents the net commodity contract liability arising from recognition of fair values as of September 30, 2025, scheduled by the source of fair value and contractual settlement dates of the underlying positions.

We have engaged in natural gas hedging activities to mitigate the risk of higher or lower wholesale electricity prices that have corresponded to increases or declines in natural gas prices. When natural gas prices are elevated or depressed, we continue to seek opportunities to manage our wholesale power price exposure through hedging activities, including forward wholesale and retail electricity sales.

Estimated hedging levels for generation volumes in our Texas, East, and West segments as of September 30, 2025 were as follows: