Self-employed tax calculator

How self-employed tax is worked out

As a sole trader you pay tax on your profit, which is your income minus your allowable business expenses. Two things come off that profit: Income Tax and Class 4 National Insurance.

Income Tax (2026/27). The first £12,570 is your personal allowance, taxed at 0%. From £12,571 to £50,270 you pay 20%. From £50,271 to £125,140 you pay 40%. Above £125,140 you pay 45%. The personal allowance also tapers away once profit passes £100,000: it drops by £1 for every £2 above, and reaches zero at £125,140.

Class 4 National Insurance. You pay 6% on profit between £12,570 and £50,270, then 2% on anything above.

Class 2 National Insurance. Nothing to pay, but it's worth understanding why. If your profit is £7,105 or more, Class 2 is treated as paid: you get the National Insurance record without the bill. Below £7,105 you owe nothing either, but you can choose to pay it voluntarily at £3.65 a week to keep your record intact for the State Pension. Class 2 was not abolished; it stopped being compulsory.

This tool assumes your self-employment is your only income and uses England's rates (Scotland has its own income tax bands). Set the money aside as you earn so the January tax bill is never a shock. New to this? Start with our guide on registering as self-employed and the self-assessment return.

Rates and thresholds checked against GOV.UK on 20 July 2026: Income Tax rates, self-employed National Insurance and student loan repayment.