MASTEC INC

Note 11 –Income Taxes

In determining the quarterly provision for income taxes, management uses an estimated annual effective tax rate based on forecasted annual pre-tax income, permanent tax differences, statutory tax rates and tax planning opportunities in the various jurisdictions in which the Company operates. The effect of significant discrete items is separately recognized in the quarter(s) in which they occur. The Company’s consolidated effective tax rates were 23.8% and 21.3% for the three months ended September 30, 2026 and 2025, respectively, and 24.2% and 21.2% for the nine months ended September 30, 2026 and 2025, respectively. The Company’s effective tax rate for the nine months ended September 30, 2026 included income tax benefits primarily due to the vesting of share-based payment awards and return-to-provision adjustments resulting from the finalization of the Company’s 2025 federal tax return, offset, in part, by the effects of a higher state income tax rate. For the nine months ended September 30, 2025, the Company’s effective tax rate included income tax benefits primarily due to the reversal of uncertain tax position liabilities related to a state audit and the release of valuation allowances on certain deferred tax assets that were no longer necessary, offset, in part, by an increase in income tax expense due to higher pre-tax income.

On July 4, 2025, new tax legislation was signed into law, known as the One Big Beautiful Bill Act (the “OBBBA”), which makes changes to certain U.S. corporate tax provisions, many of which become effective later in 2026 and thereafter. The Company has undertaken efforts to reasonably estimate the impact of the provisions of the new law and expects that there will be no material impact on the consolidated financial statements.