Hong Life CalculatorsUnderstanding the effective corporate tax rate calculator — concept and principle
This calculator works out a company's effective tax rate (ETR), the income tax expense as a share of profit before tax, and compares it with the statutory rate. It also shows the tax at the statutory rate, the gap in money and percentage points, profit after tax and the cash tax rate. Analysts, finance teams and students use it to understand why a company's tax bill differs from the headline rate.
How it is calculated
- Effective tax rate (%) = income tax expense ÷ profit before tax × 100
- Tax at the statutory rate = profit before tax × statutory rate
- Gap = income tax expense − tax at the statutory rate
- Effective minus statutory = ETR − statutory rate (percentage points)
- Profit after tax = profit before tax − income tax expense
- Cash tax rate (%) = income taxes paid in cash ÷ profit before tax × 100
Tax expense includes current and deferred tax, taken from the same income statement as the profit.
The principle
The statutory rate is the rate in the tax law; the effective rate is what the accounts actually show. They differ because taxable profit is not the same as accounting profit. Tax credits and tax-exempt income lower the ETR; non-deductible expenses and higher foreign rates raise it; losses and one-off items can push it either way. Under IAS 12, companies explain this gap in a tax-rate reconciliation note. The cash tax rate differs again because deferred tax and payment timing move tax between years.
Worked example
Defaults: profit before tax 1,000,000; tax expense 230,000; statutory rate 21%; cash taxes paid 190,000.
- ETR = 230,000 ÷ 1,000,000 × 100 = 23%.
- Tax at statutory rate = 1,000,000 × 21% = $210,000.
- Gap = 230,000 − 210,000 = $20,000, or 2 percentage points.
- Profit after tax = 1,000,000 − 230,000 = $770,000.
- Cash tax rate = 190,000 ÷ 1,000,000 × 100 = 19%.
| Profit before tax (from the income statement) | Effective tax rate |
|---|---|
| 250,000 | 92% |
| 500,000 | 46% |
| 750,000 | 30.7% |
| 1e+06 | 23% |
| 1.25e+06 | 18.4% |
| 1.5e+06 | 15.3% |
| 2e+06 | 11.5% |
How to read the result
An ETR above the statutory rate suggests non-deductible costs, higher-taxed foreign profits or write-offs of tax assets. One well below it suggests credits, incentives, exempt income or profits in lower-tax countries. Look at several years: a single year can be distorted by one-off items. A cash tax rate persistently below the ETR means tax is being deferred, which may reverse later.
Common mistakes
- Dividing by revenue or operating profit instead of profit before tax.
- Using only current tax and leaving out deferred tax.
- Comparing with a federal rate when local income taxes also apply.
- Calculating an ETR for a loss year, where it has no clear meaning.
Frequently asked questions
Why is my effective tax rate different from the statutory rate?
Because of credits, exempt income, non-deductible expenses, foreign tax rates, losses and one-off adjustments.
What is the difference between ETR and cash tax rate?
ETR uses tax expense, including deferred tax; the cash tax rate uses tax actually paid in the period.
Where can I find the reconciliation?
In the income tax note of the annual report, required by IAS 12 under IFRS.
Sources: Association of Corporate Treasurers, ACT Wiki, "Effective tax rate" · IFRS Foundation, IAS 12 "Income Taxes"