Effective Tax Rate
Income tax expense divided by pretax income. The tax rate the firm actually paid for the period — often different from the statutory rate due to deductions, credits, foreign-income mix, and timing differences.
When to use: Use to gauge tax efficiency and identify firms with unusual tax situations. Wide gaps from the statutory rate (e.g. US 21%) signal tax engineering, foreign-income mix, NOLs being used, or credit utilization. Multinational tech firms often run effective rates well below statutory.
Formula
Variables
| Symbol | Name | Description | Unit |
|---|---|---|---|
| EffectiveTaxRate | Effective Tax Rate | Tax expense divided by pretax income | % |
| TaxExpense | Income Tax Expense | Income tax expense for the period | $ |
| PretaxIncome | Pretax Income | Income before taxes (EBT) | $ |
Real-Life Examples
Example 1: Multinational Tech
Pretax income $1,000M, income tax expense $150M.
Given
Step-by-Step
15% effective tax rate — well below the US 21% statutory rate. Common for multinationals with significant foreign income taxed at lower rates, or firms with large R&D credits. Investigate the gap before assuming it's sustainable — tax-law changes can move it materially.
Frequently Asked Questions
Foreign income mix, R&D credits, carryforward NOLs, deferred tax adjustments, special low-tax structures, valuation allowances. Firms disclose major drivers in the tax footnote; large or volatile gaps warrant a read.
Sustainable low effective rates increase net income and free cash flow — yes, good. But low rates from one-time items (NOL utilization that runs out, tax credits that sunset) inflate current earnings without persisting. Distinguish recurring from non-recurring drivers.