Effective Rate
The average rate of tax you pay across all your income, calculated by dividing your total tax bill by your gross income. Unlike the marginal rate, the effective rate gives a truer picture of your overall tax burden. Because the UK tax system is progressive, your effective rate will always be lower than your highest marginal rate.
How it works
Your effective rate blends together every band your income passes through — the 0% on your Personal Allowance, the 20% basic rate, and any higher-rate tax — into a single average figure that reflects your actual tax burden as a percentage of everything you earn. It's the number that best answers 'what proportion of my income goes to tax overall', as opposed to the marginal rate, which only tells you the rate on your very last pound earned.
Because the Personal Allowance and lower bands are taxed at 0% and 20% before any higher-rate tax applies, your effective rate will always sit below your marginal rate for as long as the UK income tax system remains progressive. This gap is often much bigger than people expect — someone paying 40% tax on their top slice of income can still have an effective rate well below that once the tax-free and basic-rate portions are averaged in.
Effective rate is useful for comparing your overall tax burden year to year or against other people, while marginal rate is the number that actually matters for decisions like whether an extra hour of overtime, a bonus, or a pension contribution is worth it — the two serve different purposes and shouldn't be confused.
Example: Effective rate versus marginal rate
Suppose you earn £60,000. Your first £12,570 is tax-free under the Personal Allowance. The next £37,700 (up to the £50,270 higher-rate threshold) is taxed at 20%: £37,700 × 20% = £7,540. The remaining £9,730 is taxed at 40%: £9,730 × 40% = £3,892.
Total tax is £7,540 + £3,892 = £11,432. Your effective rate is £11,432 ÷ £60,000 = about 19.1% — noticeably lower than your 40% marginal rate on the last pound you earned.
Frequently asked questions
Why is my effective tax rate lower than my income tax bracket?
Because your bracket only describes the rate on your last pound of income, while your effective rate averages in the 0% Personal Allowance and any lower bands that applied to the rest of your earnings.
Does effective rate include National Insurance?
Not by default — effective rate usually refers to income tax alone, though you can calculate a broader combined effective rate by adding National Insurance and any student loan repayments into the total deducted.
Is a lower effective rate always better for take-home pay?
Not necessarily on its own — effective rate only measures the proportion of income taken in tax, so two people with very different gross incomes can have the same effective rate but very different amounts of money left over.
Related Terms
Marginal Rate
The rate of tax paid on the next pound of income you earn, which determines the tax cost or saving of earning slightly more or less.
Basic Rate
The standard income tax rate of 20% applied to taxable income between the Personal Allowance and the higher-rate threshold, currently £12,571 to £50,270 in England, Wales, and Northern Ireland.
Higher Rate
The income tax rate of 40% applied to taxable income above £50,270 up to £125,140 in England, Wales, and Northern Ireland.
Additional Rate
The highest income tax rate in England, Wales, and Northern Ireland, charged at 45% on taxable income above £125,140.
Taxable Income
The portion of your total income that is actually subject to income tax after deducting the Personal Allowance and any other reliefs or deductions you are entitled to.
Try the calculator
Use our free tool to see how effective rate affects your tax.