Bonus Tax Calculator UK 2025–26
Enter your annual salary and bonus amount to see exactly how much of your bonus you keep after income tax and National Insurance for 2025–26. Supports England, Wales, Northern Ireland, and Scotland.
How bonuses are taxed in the UK
UK bonuses are treated as earnings for income tax and National Insurance purposes. They are not taxed at a special flat rate — instead, they are added to your other income for the year and taxed at the marginal rates that apply to the top slice of your total income.
Marginal rate and why it matters
Your marginal rate is the rate applied to your last pound of income. If your salary of £40,000 puts you entirely in the basic rate band, but a £15,000 bonus takes your income to £55,000, the portion of the bonus above the higher rate threshold (£50,270) is taxed at 40%. The calculator calculates tax with and without the bonus to determine exactly how much income tax and NI is attributable to the bonus itself.
Personal allowance taper on high incomes
If your total income exceeds £100,000, your personal allowance reduces by £1 for every £2 of income above that threshold. This creates an effective marginal rate of 60% on income between £100,000 and £125,140 — meaning a bonus in that range is particularly costly from a tax perspective. Salary sacrifice into a pension is often the most effective mitigation.
Scottish income tax on bonuses
Scottish taxpayers pay the same employee NI as the rest of the UK, but Scottish income tax rates and bands apply to the income portion of the bonus. Scotland has six tax bands compared to three in the rest of the UK, with the intermediate rate (21%) and advanced rate (45%) applicable at lower income thresholds than the corresponding higher and additional rates in England and Wales.
Frequently asked questions
Why is my bonus taxed more than my regular salary?
Your bonus is not technically taxed at a higher rate than equivalent salary — it is taxed at your marginal rate, the same rate that applies to the top slice of your regular pay. However, because your bonus sits on top of your salary, the entire bonus amount may fall in a higher tax band than most of your regular monthly pay. For example, if your salary puts you in the basic rate band but your bonus pushes your total income above £50,270, part of the bonus is taxed at 40%.
Can I reduce the tax on my bonus through salary sacrifice?
Yes — if your employer allows it, you can sacrifice some or all of your bonus into a pension via salary sacrifice. This removes the bonus amount from your taxable income and NI base, so you pay no income tax or NI on the sacrificed amount. The bonus goes into your pension instead of your bank account. This is particularly effective if the bonus pushes your income above a tax band threshold.
Is my bonus subject to National Insurance?
Yes — bonuses are treated as earnings for NI purposes and are subject to Class 1 employee NI at the same marginal rates as regular pay. If your total earnings (salary plus bonus) exceed the upper earnings limit of £50,000, the NI rate above that threshold is 2% rather than 8%. The calculator shows the exact NI deduction on your bonus separately.
Does my bonus affect my personal allowance?
If your total income (salary plus bonus) exceeds £100,000, your personal allowance begins to taper at £1 for every £2 above that threshold. This creates an effective marginal rate of 60% on income between £100,000 and £125,140. The calculator accounts for this taper when calculating the income tax on your bonus.
How does HMRC tax a bonus paid in a lump sum versus spread across the year?
Through PAYE, your employer may apply the lump-sum bonus to a single month's payroll, which can temporarily push you into a higher band on a monthly basis. However, HMRC reconciles this at year end — you will not pay more tax overall than if the bonus had been spread evenly. If you were overtaxed during the year, HMRC will adjust your code or issue a refund.
Related calculators
This calculator provides estimates only. Results are based on the 2025–26 tax year. Credibrate is not a tax adviser. For personalised advice speak to a qualified accountant.