Bonus Tax Calculator

See how much of your bonus you actually keep after tax, NI, student loans, and pension. Updated for the 2025/26 tax year.

Bonus take-home

£3,600

72% of your bonus

£
£10k£300k
£
£0£100k

£5,000 bonus — you take home

£3,600

72% of your bonus

Great — you keep most of your bonus at the basic rate.

Where does your bonus go?

Gross bonus
£5,000
Income tax
£1,000
National Ins.
£400
Take-home
£3,600

Keep

72%

Marginal rate

28%

Total deducted

£1,400

Bonus tax breakdown comparing salary only, salary with bonus, and marginal bonus cost
Salary onlyWith bonusBonus cost
Gross income£40,000£45,000+£5,000
Income tax£5,486£6,486+£1,000
National Insurance£2,194£2,594+£400
Take-home£32,320£35,920+£3,600

Salary sacrifice tip

If you sacrifice your entire £5,000 bonus into your pension via salary sacrifice, you'd save £1,400 in tax and National Insurance. The money goes to your pension pot instead of HMRC.

How are bonuses taxed in the UK?

Your bonus is added to your regular salary and taxed as normal income. There's no special "bonus tax rate" — it's income tax, National Insurance, and any student loan repayments at the marginal rates determined by your total annual earnings.

Why does it feel so heavily taxed? Because your salary already uses up your Personal Allowance (£12,570 tax-free) and basic rate band. Your bonus sits entirely on top, so every penny is taxed at your highest marginal rate.

Emergency tax: Sometimes PAYE applies "Month 1" rules to bonuses, temporarily over-deducting. If this happens, you'll be refunded automatically through your regular payroll within a few months, or via a P800 from HMRC at year-end.