QUANTA SERVICES, INC.

8. INCOME TAXES:

Quanta’s effective tax rates for the three months ended March 31, 2026 and 2025 were 9.7% and 21.1%. The lower effective tax rate for the three months ended March 31, 2026 was primarily due to a $32.2 million increase in tax benefit from vested equity incentive awards.

As of March 31, 2026, the total amount of unrecognized tax benefits relating to uncertain tax positions was $78.6 million, a net increase of $4.2 million from December 31, 2025, which primarily resulted from current year positions. Quanta’s consolidated federal income tax return for tax year 2024 is currently under examination by the Internal Revenue Service (IRS), and the consolidated federal income tax returns for tax years 2022 to 2023 remain open to examination by the IRS, as the applicable statute of limitations periods have not yet expired. Additionally, various state and foreign tax returns filed by Quanta and certain subsidiaries for multiple periods remain under examination by various U.S. state and foreign tax authorities. Quanta does not consider any U.S. state in which it does business to be a major tax jurisdiction.