FAIR VALUE MEASUREMENTS
Fair value measurements are based upon inputs that market participants use in pricing an asset or liability, which are characterized according to a hierarchy that prioritizes those inputs based on the degree to which they are observable. Observable inputs represent market data obtained from independent sources, whereas unobservable inputs reflect our own market assumptions. We categorize our assets and liabilities recorded at fair value based upon the following fair value hierarchy as defined by GAAP:

Level 1 valuations use quoted prices in active markets for identical assets or liabilities that are accessible at the measurement date.

Level 2 valuations use over-the-counter broker quotes, quoted prices for similar assets or liabilities that are corroborated by correlations or other mathematical means, and other valuation inputs such as interest rates and yield curves observable at commonly quoted intervals.

Level 3 valuations use unobservable inputs for the asset or liability, typically reflecting our estimate of assumptions that market participants would use in pricing the asset or liability. The fair value is therefore determined using model-based techniques, including discounted cash flow models.

The fair value input hierarchy level to which an asset or liability measurement in its entirety falls is determined based on the lowest level input that is significant to the measurement.

Assets and Liabilities Measured at Fair Value on a Recurring Basis

Assets and liabilities measured at fair value on a recurring basis consisted of the following at the respective balance sheet dates shown below:
December 31, 2025December 31, 2024
Level
1
Level
2
Level
3
Reclass (a)TotalLevel
1
Level
2
Level
3
Reclass (a)Total
(in millions)
Assets:
Commodity contracts (b)$2,162 $437 $573 $$3,180 $1,923 $462 $841 $$3,231 
Interest rate swaps (b)— 17 — 18 — 96 — — 96 
NDTs – equity securities (c)(d)1,761 — — 1,761 1,560 — — 1,560 
NDTs – debt securities (c)(e)117 1,971 — 2,088 83 1,976 — 2,059 
Sub-total$4,040 $2,425 $573 $7,047 $3,566 $2,534 $841 $6,946 
Assets measured at net asset value (f):
NDTs – equity securities (c)(d)(f)806 821 
NDTs – debt securities (c)(e)(f)329 — 
NDTs - other investments (c)(f)28 — 
Total assets$8,210 $7,767 
Liabilities:
Commodity contracts (b)$3,060 $846 $1,842 $$5,756 $2,118 $975 $1,593 $$4,691 
Interest rate swaps (b)— 21 — 22 — 27 — — 27 
Total liabilities$3,060 $867 $1,842 $$5,778 $2,118 $1,002 $1,593 $$4,718 
____________
(a)Fair values for each level are determined on a contract basis, but certain contracts are in both an asset and a liability position. This reclassification represents the adjustment needed to reconcile to the gross amounts presented in the consolidated balance sheets.
(b)See Note 13 for additional information.
(c)NDT assets represent securities held for the purpose of funding the future retirement and decommissioning of our nuclear generation facilities. These investments include equity, debt and other securities consistent with investment rules established by the NRC and the PUCT. The NDT investments are included in Investments in the consolidated balance sheets. There were no significant concentrations of credit risk from an individual counterparty or groups of counterparties in our NDT portfolio as of December 31, 2025.
(d)The investment objective for NDT equity securities is to invest tax efficiently and to match the performance of the S&P 500 and Russell 3000 Indices for U.S. equity investments and the MSCI EAFE and MSCI All Country World ex-US Indices for non-U.S. equity investments.
(e)The investment objective for NDT debt securities is to invest in a diversified, high quality, tax efficient portfolio. The debt securities are weighted with government and investment grade corporate bonds. Other investable debt securities include, but are not limited to, municipal bonds, high yield bonds, securitized bonds, non-U.S. developed bonds, emerging market bonds, loans and treasury inflation-protected securities. The debt securities had an average coupon rate of 4.02% and 3.99% as of December 31, 2025 and 2024, respectively, and an average maturity of eight years and seven years as of December 31, 2025 and 2024, respectively. NDT debt securities held as of December 31, 2025 mature as follows: $848 million in one to five years, $1.114 billion in five to 10 years and $455 million after 10 years.
(f)Net asset value is a practical expedient used for the classification of assets that do not have readily determinable fair values and therefore are not classified in the fair value hierarchy. This amount is presented to permit reconciliation of this table to the amounts presented in the consolidated balance sheets.

The following tables present the fair value of Level 3 assets and liabilities by major contract type and the significant unobservable inputs used in the valuations as of December 31, 2025 and 2024:
December 31, 2025
Fair Value
Contract Type (a)AssetsLiabilitiesTotal, NetValuation TechniqueSignificant Unobservable InputRange (b)Average (b)
(in millions)
Electricity purchases and sales$269 $(1,607)$(1,338)Income ApproachHourly price curve shape (c)$— to$95 $48 
MWh
Illiquid delivery periods for hub power prices (d)$25 to$135 $80 
MWh
Market Heat Rates (d)$25 to$130 $78 
MWh
Options— (177)(177)Option Pricing ModelNatural gas to power correlation (e)15 %to100 %58 %
Power and natural gas volatility (e)%to1,120 %563 %
Financial transmission rights/Congestion revenue rights277 (34)243 Market Approach (f)Illiquid price differences between settlement points (g)$(12)to$25 $
MWh
Natural gas16 (24)(8)Income ApproachNatural gas basis (h)$(2)to$14 $
MMBtu
Illiquid delivery periods (i)$to$$
MMBtu
Other (j)11 — 11 
Total$573 $(1,842)$(1,269)
December 31, 2024
Fair Value
Contract Type (a)AssetsLiabilitiesTotal, NetValuation TechniqueSignificant Unobservable InputRange (b)Average (b)
(in millions)
Electricity purchases and sales$606 $(1,399)$(793)Income ApproachHourly price curve shape (c)$— to$95 $48 
MWh
Illiquid delivery periods for hub power prices and Heat Rates (d)$25 to$140 $83 
MWh
Market Heat Rates (d)
$30 $150 $90 
MWh
Options(139)(133)Option Pricing ModelNatural gas to power correlation (e)10 %to100 %55 %
Power and natural gas volatility (e)%to710 %358 %
Financial transmission rights/Congestion revenue rights190 (25)165 Market Approach (f)Illiquid price differences between settlement points (g)$(35)to$20 $(8)
MWh
Natural gas29 (30)(1)Income ApproachNatural gas basis (h)$— to$10 $
MMBtu
Illiquid delivery periods (i)$— to$$
MMBtu
Other (j)10 — 10 
Total$841 $(1,593)$(752)
____________
(a)(i) Electricity purchase and sales contracts include power and Heat Rate positions in ERCOT, PJM, ISO-NE, NYISO, MISO, and CAISO regions, (ii) Options consist of physical electricity options, spread options and natural gas options, (iii) Forward purchase contracts (swaps and options) used to hedge electricity price differences between settlement points are referred to as congestion revenue rights (CRRs) in ERCOT and financial transmission rights (FTRs) in PJM, ISO-NE, NYISO, and MISO regions, and (iv) Natural gas contracts include swaps and forward contracts.
(b)The range of the inputs may be influenced by factors such as time of day, delivery period, season, and location. The average represents the arithmetic average of the underlying inputs and is not weighted by the related fair value or notional amount.
(c)Primarily based on the historical range of forward average hourly ERCOT North Hub and ERCOT South and West Zone prices.
(d)Primarily based on historical forward ERCOT and PJM power prices and ERCOT Heat Rate variability.
(e)Primarily based on the historical forward correlation and volatility within ERCOT and PJM.
(f)While we use the market approach, there is insufficient market data for the inputs to the valuation to consider the valuation liquid.
(g)Primarily based on the historical price differences between settlement points within ERCOT hubs and load zones.
(h)Primarily based on the historical forward PJM and Northeast natural gas basis prices and fixed prices.
(i)Primarily based on the historical forward natural gas fixed prices.
(j)Other includes contracts for coal and environmental allowances.
The following table presents the changes in fair value of Level 3 assets and liabilities:
Year Ended December 31,
202520242023
(in millions)
Net liability balance at beginning of period$(752)$(1,044)$(1,219)
Total unrealized valuation gains (losses)(548)(175)(765)
Purchases, issuances and settlements (a):
Purchases313 266 222 
Issuances(25)(26)(30)
Settlements(147)137 136 
Transfers into Level 3 (b)(8)(15)(48)
Transfers out of Level 3 (b)308 118 660 
Net liabilities assumed in connection with acquisitions(410)(13)— 
Net change(517)292 175 
Net liability balance at end of period$(1,269)$(752)$(1,044)
Unrealized valuation losses relating to instruments held at end of period$(555)$(416)$(676)
____________
(a)Settlements reflect reversals of unrealized mark-to-market valuations previously recognized in net income. Purchases and issuances reflect option premiums paid or received, including CRRs and FTRs.
(b)Includes transfers due to changes in the observability of significant inputs. All Level 3 transfers during the periods presented are in and out of Level 2. For the year ended December 31, 2025, transfers into Level 3 primarily consist of power derivatives where forward pricing inputs have become unobservable and transfers out of Level 3 primarily consist of power derivatives where forward pricing inputs have become observable. For the year ended December 31, 2024, transfers into Level 3 primarily consist of power derivatives where forward pricing inputs have become unobservable and transfers out of Level 3 primarily consist of power and natural gas derivatives where forward pricing inputs have become observable.

Assets and Liabilities Recorded on a Non-Recurring Basis

Certain assets and liabilities are measured at fair value on a nonrecurring basis. These assets and liabilities are not measured at fair value on an ongoing basis, but are subject to fair value adjustments in certain circumstances. These assets and liabilities can include inventories, assets acquired and liabilities assumed in business combinations, goodwill and other long-lived assets that are written down to fair value when they are determined to be impaired or held for sale.

The Energy Harbor Merger and the Lotus Acquisition were accounted for under the acquisition method which requires all assets acquired and liabilities assumed in the acquisition be recorded at fair value at the acquisition date. See Note 2 for additional information.

Fair Value of Debt
December 31, 2025December 31, 2024
InstrumentFair Value HierarchyCarrying AmountFair
Value
Carrying AmountFair
Value
(in millions)
Long-term debt under the Vistra Operations Credit FacilitiesLevel 2$2,417 $2,459 $2,435 $2,478 
BCOP Credit FacilityLevel 3859 872 344 367 
Vistra Zero Term Loan B FacilityLevel 2687 688 685 697 
Vistra Operations Senior NotesLevel 212,620 12,955 12,366 12,428 
Energy Harbor Revenue BondsLevel 2416 433 414 431 
Equipment Financing AgreementsLevel 345 45 54 53 
Forward Repurchase ObligationLevel 3632 632 1,335 1,335 
We determine fair value in accordance with accounting standards. We obtain security pricing from an independent party who uses broker quotes and third-party pricing services to determine fair values. Where relevant, these prices are validated through subscription services such as Bloomberg.

Historical Timeline

Fiscal YearFiled
2025Feb 27, 2026Showing above
2024Feb 28, 2025
2023Feb 29, 2024
2022Mar 1, 2023
2021Feb 25, 2022
2020Feb 26, 2021
2019Feb 28, 2020
2018Feb 28, 2019
2017Feb 26, 2018

About Fair Value Disclosures

Fair value disclosures classify all assets and liabilities measured at fair value into a three-level hierarchy: Level 1 (quoted market prices), Level 2 (observable inputs like yield curves), and Level 3 (unobservable inputs requiring management estimates). The proportion of Level 3 assets directly reflects how much of the balance sheet depends on internal models rather than market evidence.

Key signals: a growing Level 3 balance relative to total fair-value assets increases valuation uncertainty and earnings volatility risk. Watch for transfers between levels — assets moving from Level 2 to Level 3 often signal deteriorating market liquidity. Unrealized gains and losses on Level 3 positions flow through earnings or other comprehensive income, so large swings deserve scrutiny. For financial institutions, examine the sensitivity disclosures that show how Level 3 valuations change under alternative assumptions. Compare the fair value of debt against its carrying amount to gauge hidden leverage.