Self-Employed Tax Calculator (Sole Trader, UK)
Enter your yearly profit to see the tax and National Insurance you owe and what you keep.
| Item | Per year | Per month | % of profit |
|---|---|---|---|
| Income tax | £7,486 | £624 | 15% |
| Class 4 National Insurance | £2,246 | £187 | 4.5% |
| Take-home | £40,268 | £3,356 | 80.5% |
Set aside about £9,732 (19% of profit) for your tax bill.
How self-employed tax works
If you are a sole trader you pay tax on your profit (what you earn minus allowable business expenses), not on your turnover. You work this out and pay through Self Assessment.
- Income tax at the same rates as employees: 0% on the first £12,570, 20% up to £50,270, 40% up to £125,140 and 45% above.
- Class 4 National Insurance: 6% on profits between £12,570 and £50,270, and 2% above that.
- Class 2: if your profits are £7,105 or more, you do not have to pay Class 2, and your year still counts for the State Pension. Below that you can pay voluntarily at £3.65 a week.
On profits of £50,000 you pay £7,486 income tax and £2,246 Class 4 NI, leaving £40,268.
Payments on account
If your Self Assessment bill is over £1,000, HMRC usually asks for payments on account, two advance payments (31 January and 31 July) of half your last bill each, on top of your balancing payment on 31 January. This means your first year can feel like paying two bills. Setting aside 25% to 30% of profit each month avoids a shock.
Things that reduce your tax
- Allowable expenses such as stock, travel, equipment and professional fees.
- The £1,000 trading allowance, which can replace actual expenses on small incomes.
- Pension contributions, which get tax relief.
This calculator ignores expenses against the trading allowance, pension contributions and other income. It assumes a standard Personal Allowance.
Sources: GOV.UK: Self-employed National Insurance rates, GOV.UK: Income Tax rates. Figures last checked on 8 October 2026.
Frequently asked questions
How much tax does a sole trader pay on £50,000?
About £9,732: £7,486 income tax plus £2,246 Class 4 National Insurance, leaving £40,268.
When do I pay tax as self-employed?
You file a Self Assessment return by 31 January after the tax year ends and pay the bill by the same date, with payments on account on 31 January and 31 July if your bill is over £1,000.
Do I pay National Insurance if self-employed?
Yes, Class 4 on profits above £12,570. Class 2 is no longer due once your profits reach the small profits threshold.
Do I need to register as self-employed?
Yes, with HMRC, if you earn more than £1,000 in a tax year from self-employment (the trading allowance).
Related guides
More from UK Answers
Figures are for the 2026/27 tax year from official sources and are estimates for guidance only, not financial or legal advice. Printed from ukanswers.co.uk.