Salary Breakdown Calculator
See exactly where your UK salary goes — income tax, National Insurance, pension, and your real take-home pay.
On a £50,000 UK salary you take home approximately £3,091/month after income tax and National Insurance — an effective rate of 21%.
£12,570
personal allowance — the amount you earn completely tax-free every year (2025/26)
28%
combined basic-rate burden: 20% income tax + 8% National Insurance on most taxable income
60%
effective marginal rate inside the £100k–£125,140 personal allowance taper trap
How UK salary tax is calculated
The UK uses a progressive PAYE (Pay As You Earn) system — you pay a higher rate only on income above each threshold, not on your whole salary. The calculation has three stages:
Deduct pension contributions
Pension contributions reduce the income that both income tax and National Insurance are calculated on.
Apply income tax bands
Each slice of income is taxed at the rate for that band — 0% on the personal allowance, then 20%, 40%, or 45% on higher slices.
Add National Insurance
NI is calculated separately — 8% on earnings between £12,570 and £50,270, then 2% on anything above.
UK income tax and National Insurance rates (2024/25)
These are the PAYE bands applied to employees in England, Wales, and Northern Ireland. Scotland has its own income tax rates.
Income Tax
National Insurance (Class 1)
The personal allowance tapers from £100,000 to £125,140, creating an effective 60% marginal rate on that band.
How pension contributions reduce your UK tax
Contributing to a workplace pension via salary sacrifice reduces the income that both income tax and National Insurance are calculated on — so you save tax at your marginal rate on every pound you contribute.
£40,000 salary
£4,000/yr (10%)
~£1,120 saved
20% income tax + 8% NI = 28% effective saving on that slice.
£55,000 salary
£5,500/yr (10%)
~£2,310 saved
40% income tax + 2% NI = 42% effective saving on the higher-rate slice.
£105,000 salary
£5,000/yr
~£3,100 saved
Bringing income below £100k restores part of the personal allowance — effective saving rate up to 62%.
The annual pension allowance in 2024/25 is £60,000 (or 100% of earnings, whichever is lower). The examples above assume salary sacrifice — if you contribute from net pay instead, you only receive income tax relief, not NI savings.
The £100,000 personal allowance trap
The UK personal allowance (£12,570) tapers away for income above £100,000 — at £1 for every £2 of extra income. This means:
Effective 60% marginal rate
Between £100,000 and £125,140 you pay 40% income tax on your earnings plus lose the personal allowance at the same time. The combined effect is a 60% effective marginal rate on that band.
How to avoid it
Making pension contributions that bring your adjusted net income below £100,000 restores the full personal allowance. This is one of the most tax-efficient things a higher earner can do.
What this means for you
Three things that change how UK tax actually works in practice.
You don’t pay 40% on your whole salary
If you earn £55,000, only the £4,730 above £50,270 is taxed at 40%. Everything below that is taxed at 20% or 0%. Your effective rate is well below your marginal rate.
NI is charged on top of income tax
National Insurance is a separate payroll levy calculated independently. Most basic-rate earners pay 20% income tax + 8% NI on their taxable income — a combined 28% on that band, not just 20%.
The £100k trap is real
Between £100,000 and £125,140 your personal allowance tapers away. For every £2 above £100k you lose £1 of allowance — creating an effective 60% marginal rate. Pension contributions can avoid this entirely.
What you can do next
Practical steps to legally reduce your UK tax and National Insurance bill.
Check your tax code
HMRC issues a tax code telling your employer how much to deduct. An incorrect code — common after a job change, benefits update, or P11D filing — can mean overpaying thousands. Check your payslip and verify via the HMRC Personal Tax Account.
Use salary sacrifice for your pension
Salary sacrifice contributions reduce both income tax and National Insurance. At the basic rate you save 28p per pound sacrificed (vs 20p from a personal pension). At the higher rate, the combined saving is 42p per pound.
Avoid the £100k trap
If your income is near or above £100,000, pension contributions that bring adjusted net income below that threshold restore your full personal allowance. The effective saving rate can exceed 60p per pound — the most tax-efficient move available to most UK earners.
Frequently asked questions
How much income tax do I pay on a £50,000 salary?
On a £50,000 salary you pay 20% on income between £12,570 and £50,000 — that's £7,486. You also pay 8% National Insurance on earnings between £12,570 and £50,270, which adds around £3,014. Combined effective rate is about 21%.
What is National Insurance and how much do I pay?
National Insurance (NI) is a UK payroll levy separate from income tax. Employees pay 8% on earnings between £12,570 and £50,270, and 2% above £50,270 (2024/25 rates).
Does a pension contribution reduce National Insurance?
Only via salary sacrifice. If your employer deducts pension contributions from your gross pay before payroll runs, both income tax and NI are reduced. If you contribute to a personal pension from net pay, you only get income tax relief.
What is the difference between my marginal and effective tax rate?
Your marginal rate is the rate on your top slice of income. Your effective rate is the average across all your income — always lower. A £60,000 earner pays 40% on income above £50,270 but their overall effective rate is typically 26–28%.
What is the personal allowance trap at £100,000?
Between £100,000 and £125,140 your personal allowance tapers to zero, creating a 60% effective marginal tax rate. Pension contributions to bring adjusted net income below £100,000 can fully avoid this.
Why doesn't this calculator include Scottish income tax?
Scotland has its own income tax rates with different bands. This calculator uses England, Wales, and Northern Ireland PAYE rates. Scottish taxpayers will get different results and should use HMRC's tax calculator.
Disclaimer
This calculator provides estimates based on 2024/25 HMRC rates for England, Wales, and Northern Ireland. It does not account for Scottish income tax, student loan repayments, marriage allowance, employer benefits, or other personal tax circumstances. Always verify with a qualified tax adviser before making financial decisions.