Self-Employed Tax Calculator UK

Last updated: October 2026

For UK sole traders in 2026/27, enter your profit and the calculator applies income tax at 20 percent above the £12,570 personal allowance, plus Class 4 National Insurance at 6 percent between £12,570 and £50,270 and 2 percent above that. Class 2 is treated as paid on profits of £7,105 or more.

What does the self-employed tax calculator do?

This free calculator works out the full UK tax bill for sole traders in the 2026/27 tax year (6 April 2026 to 5 April 2027): income tax by band, Class 4 National Insurance, and your Class 2 status. Enter your annual profit after expenses and it shows every charge, your total bill and your take-home pay.

How to use it

1. Enter your annual self-employed profit in pounds: your turnover minus allowable business expenses, not the turnover itself.
2. Press “Calculate self-employed tax” to see your income tax broken down by band, your Class 4 National Insurance, and whether your Class 2 contributions count as paid.
3. Read the total tax and NI bill and your net take-home pay, then use “Copy result” to save the figures for your records.

The 2026/27 rates used

All figures verified against official sources in October 2026. Income tax (England, Wales and Northern Ireland): £12,570 personal allowance, 20% basic rate to £50,270, 40% higher rate to £125,140, 45% additional rate above. The allowance tapers by £1 for every £2 earned over £100,000. Class 4 NICs: 6% on profits between £12,570 and £50,270, 2% above £50,270 (gov.uk National Insurance rates). Class 2: no compulsory payment since April 2024. Profits of £7,105 or more are treated as paid at no cost, protecting your State Pension record; below that you can pay voluntary Class 2 at £3.65 a week (£189.80 a year).

Worked example

A sole trader with £30,000 of profit in 2026/27: income tax is 20% of (£30,000 – £12,570) = £3,486. Class 4 NICs are 6% of the same £17,430 = £1,045.80. Class 2 is treated as paid, so nothing extra. Total bill £4,531.80, take-home £25,468.20. On £60,000 of profit the bill rises to £13,888.60 (£11,432 income tax + £2,456.60 Class 4), leaving £46,111.40.

What is not included

The calculator uses a standard personal allowance and does not account for the trading allowance, pension relief, student loan repayments, payments on account, Class 1 NICs from any employed work alongside your business, or Scottish taxpayer status. If you are a Scottish taxpayer, see our guide to self-employed tax in Scotland for the Scottish bands. It is an estimate, not tax advice.

Wrong tool? Find the right one

After a plain income tax figure with no National Insurance, use the UK income tax calculator. Running a limited company and taking dividends instead, use the UK dividend tax calculator.

Frequently asked questions

Do I still pay Class 2 National Insurance?

Not as a separate compulsory charge. Since April 2024, if your profits are £7,105 or more, HMRC treats your Class 2 contributions as paid and your State Pension record is protected at no cost. Below £7,105 you can pay voluntary Class 2 at £3.65 a week.

Is Class 4 charged on turnover or profit?

On profit: turnover minus allowable business expenses. Two freelancers invoicing the same amount can owe very different Class 4 bills if their costs differ, which is why the calculator asks for profit, not turnover.

Why is my bill higher than just income tax?

Class 4 NICs are charged on top of income tax, not instead of it. At £30,000 of profit, Class 4 adds £1,045.80 to the £3,486 income tax bill. Many first-year sole traders are caught out because they budget for income tax only.

What are payments on account?

Once your Self Assessment bill exceeds £1,000, HMRC usually asks for payments on account: two advance payments toward next year’s bill, due 31 January and 31 July. Your first year can feel expensive because you pay last year’s bill plus half of next year’s at once.

I am both employed and self-employed. Does this work for me?

Partly. Your employer handles Class 1 NICs on your salary through payroll. Enter only your self-employment profit here for the Class 4 figure, but note the income tax bands apply to your combined income, so the income tax shown may be understated if you also earn a salary.

References

Official rates: Income tax rates and Personal Allowances (gov.uk), National Insurance rates and allowances (gov.uk), verified October 2026.

Related calculators: UK income tax calculator, UK dividend tax calculator, VAT calculator.