UK Income Tax Calculator

UK Income Tax is a progressive tax levied by HMRC on an individual's taxable income, which includes employment income, self-employment profits, rental income, pensions, savings interest, and dividends. For the 2024/25 tax year the system works as follows. Every UK resident receives a Personal Allowance of £12,570 — the amount you can earn completely free of income tax. Income between £12,571 and £50,270 falls in the Basic Rate band and is taxed at 20%. Income between £50,271 and £125,140 is taxed at the Higher Rate of 40%. Income above £125,140 is taxed at the Additional Rate of 45%. Crucially, the Personal Allowance is gradually withdrawn for high earners: for every £2 of income above £100,000, the allowance is reduced by £1, creating an effective 60% marginal tax rate on income between £100,000 and £125,140. Scottish residents pay Scottish Income Tax rates set by the Scottish Parliament, which differ from the rest of the UK — Scotland has five bands including a Starter Rate of 19% and an Intermediate Rate of 21%. UK Income Tax does not include National Insurance contributions, which are calculated and paid separately. The tax year runs from 6 April to 5 April each year — an historical artefact of calendar reform. Most employees pay via PAYE (Pay As You Earn), while self-employed individuals and those with complex affairs file a Self Assessment tax return.

Calkulon makes complex calculations simple — built for students and everyday problem-solvers.

1. 1Start with your total gross income from all sources (employment, self-employment, rental, pensions, savings, dividends)
2. 2Subtract your Personal Allowance (£12,570 for 2024/25) — reduced by £1 for every £2 earned above £100,000, reaching £0 at £125,140
3. 3The remaining taxable income is divided across rate bands: first £37,700 at 20% Basic Rate (income £12,571–£50,270)
4. 4Income from £50,271 to £125,140 is taxed at 40% Higher Rate
5. 5Any income above £125,140 is taxed at 45% Additional Rate
6. 6Add tax on savings income (using the savings starting rate and Personal Savings Allowance) and dividends separately at dividend rates
7. 7Subtract any tax reliefs and credits (Gift Aid, pension contributions, Marriage Allowance) to arrive at the final tax liability

• !Confusing marginal rate with average (effective) rate — your marginal rate is the rate on the last pound earned, not on all income
• !Forgetting that National Insurance is calculated separately from Income Tax
• !Ignoring the Personal Allowance taper when income approaches £100,000 — making pension contributions can be extremely tax-efficient here
• !Treating Scottish and non-Scottish rates as identical — Scottish taxpayers face different bands and rates
• !Omitting savings interest, rental income, or dividend income which must all be declared through Self Assessment
• !Missing the 31 January Self Assessment filing deadline, triggering automatic £100 penalties