UK Bonus Tax Calculator
Bonuses are taxed as ordinary income on top of your salary, so your marginal rate decides how much you keep. Enter your salary and bonus to see the breakdown.
The calculator uses your marginal Income Tax and National Insurance rates for the tax year.
How the calculation works
We believe numbers should be transparent. Here is the formula behind this calculator.
Worked example
Worked example: a £5,000 bonus on a £40,000 salary
Examples at common levels
See how the numbers change at typical input levels, using the updated for tax year 2026/27 rates.
| Scenario | Gross bonus | Income Tax on bonus | National Insurance on bonus | Total deductions | You receive from your bonus |
|---|---|---|---|---|---|
| £5,000 bonus on £40,000 salary Basic rate: 20% tax + 8% NI | £5,000.00 | £1,000.00 | £400.00 | £1,400.00 | £3,600.00 |
| £10,000 bonus on £55,000 salary Part of the bonus in the higher band | £10,000.00 | £4,000.00 | £200.00 | £4,200.00 | £5,800.00 |
| £2,000 bonus on £50,000 salary Bonus crosses the £50,270 threshold | £2,000.00 | £746.00 | £56.20 | £802.20 | £1,197.80 |
| £10,000 bonus on £100,000 salary Personal Allowance taper | £10,000.00 | £6,000.00 | £200.00 | £6,200.00 | £3,800.00 |
Important assumptions
- Bonuses are treated as ordinary income for Income Tax and NI.
- Uses your marginal rate based on your annual salary and the bonus amount.
- Student loan repayments are not deducted in this calculator.
Rates & official sources
Every calculation is based on the official rates and rules published by GOV.UK and HMRC.
Frequently asked questions
Why is so much tax taken from my bonus?
Bonuses are taxed at your marginal rate on top of your salary. If you are a basic-rate taxpayer, that is 20% plus 8% NI — but a bonus can also push you into the higher 40% band.
Can a bonus push me into a higher tax band?
Yes. If your salary plus bonus crosses £50,270, the part above the threshold is taxed at 40%. This calculator uses that exact split.
Is a bonus taxed differently to salary?
No. For Income Tax and NI it is simply extra earnings. The only difference is that it is usually paid as a lump sum in one pay period.
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View calculatorRelated guides
New to the topic? Read a plain-English guide on salary & tax, with worked examples and tips.
How UK Income Tax works
The tax-free allowance, rate bands and how PAYE takes tax from your pay.
Read the guide TaxPAYE explained
How pay as you earn collects Income Tax and NI from your salary.
Read the guide TaxUnderstanding tax bands
Basic, higher and additional rate explained with worked examples.
Read the guide TaxHow to read a payslip
Every line on your pay slip decoded — payments, deductions, year-to-date, and why a bonus month looks different.
Read the guide TaxUK tax rates and allowances 2026/27
Every UK tax rate and allowance for the 2026/27 tax year in one place — income tax, National Insurance, VAT, dividends, corporation tax, student loans and more.
Read the guide TaxHigh Income Child Benefit Charge explained
How the High Income Child Benefit Charge works — the £60,000 threshold, the 1% clawback and what you repay.
Read the guide TaxPension tax relief explained
How pension tax relief works — 20% added at source, extra relief for higher and additional-rate taxpayers, and the annual allowance.
Read the guideThese calculations are estimates for guidance only and are not professional financial, tax or legal advice. UK rates and rules change, so always verify important figures with official GOV.UK / HMRC information or speak to a qualified professional. See our full disclaimer.