Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2025
Income Tax Disclosure [Abstract]
Income Taxes	Note 11: Income Taxes Interim Income Tax Expense (Benefit) – Our income tax expense or benefit reflects a combination of income taxes in foreign jurisdictions and certain U.S. states. We have federal and state net operating loss carryforwards (“NOLs”) and non-deductible interest expense carryforwards in the U.S. that may be applied to reduce taxable income in current and future tax years. Some of these carryforwards are subject to annual usage limitations and expiration, while other state NOLs and a portion of federal NOLs do not have limitations or expiration. We carry a valuation allowance against our U.S. carryforwards, which results in no net income tax expense in our earnings in periods when additional NOLs are generated or when existing NOLs are utilized. Certain states that we operate in have rules regarding the deductibility of items that diverge from U.S. federal deductibility rules and in addition, a number of these states have placed limitations on the usage of NOLs to offset taxable income apportioned to those states. Our overall effective tax rate is affected by a number of factors, including the relative amounts of income we earn in different tax jurisdictions, tax law changes, certain non-deductible expenses, the changes in our valuation allowance and divergence of state rules from federal rules. The factors result in an effective tax rate that differs from statutory rates. For interim periods, we estimate our annual effective tax rate, exclusive of discrete items, which is derived primarily by our estimate of taxable income or losses for our applicable jurisdictions together with estimates of changes to our valuation allowance. The estimated annual effective tax rate is recorded in interim periods based on year-to-date income or loss before income taxes. Accordingly, income tax expense or benefit in quarterly periods reflects the impacts of changes to our annual effective tax rate. Because of the impacts of (i) the U.S. carryforwards’ valuation allowances, (ii) taxes in foreign jurisdictions and (iii) taxes in U.S. states that diverge from U.S. federal deductibility rules, our effective tax rate may fluctuate between a positive and a negative rate. For the nine months ended September 30, 2025, our income tax expense is comprised of $8.0 million of state income tax expense and $0.8 million of foreign income tax expense, resulting in an effective tax rate of (20.4)%. The effective tax rate was (0.9)% for the nine months ended September 30, 2024. Recent Tax Legislation – On July 4, 2025, the President signed the One Big Beautiful Bill Act (the “OBBBA”) into law. This act introduces significant changes to tax law and other areas affecting company operations, including items such as extensions of provisions previously enacted under the 2017 Tax Cuts and Jobs Act, changes to business interest deductions, or modifications to depreciation deductions and impacts on energy tax credits. We are evaluating the potential impact of the OBBBA on our financial statements.

The entire disclosure for income tax.

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Custom Truck One Source, Inc. 10-Q