Self-Employed Tax Calculator UK
Work out the income tax and Class 4 National Insurance you'll owe on your self-employment profit for 2026/27. Enter your profit after expenses to see your total bill and net profit.
Calculator
What this means
Sole traders pay income tax on profits above the personal allowance, plus Class 4 National Insurance at 6% on profits between £12,570 and £50,270 and 2% above. Class 2 NI is no longer required if your profits are above the small profits threshold.
How to use this calculator
- Enter your expected self-employed profit (income minus expenses).
- See your income tax and Class 2/4 National Insurance.
- Use it to set aside the right amount for your tax bill.
Worked example
You make £30,000 profit as a sole trader in 2026/27.
- The £12,570 personal allowance is tax-free.
- 20% income tax on £17,430 is about £3,486.
- Class 4 NI at 6% on profit above £12,570 is about £1,046.
Set aside roughly £4,500+ for income tax and National Insurance, plus any payments on account.
Who this is for
- Sole traders and freelancers planning for tax.
- People with a side hustle alongside a job.
- Anyone budgeting for a Self Assessment bill.
Tax and NI for the self-employed
Self-employed people pay income tax on their profit (income minus allowable expenses) using the same bands as employees. On top, they pay Class 4 National Insurance at 6% on profit between £12,570 and £50,270, and 2% above.
You report this through Self Assessment by 31 January. HMRC may also ask for 'payments on account' — advance instalments towards next year's bill — so your first tax bill can feel larger than expected.
Frequently asked questions
You pay income tax on your profit (income minus allowable expenses) above the personal allowance, using the same bands as employees, plus Class 4 National Insurance on profits above £12,570.
From recent tax years, self-employed people with profits above the small profits threshold no longer need to pay Class 2 NI but still get the benefit entitlement. Those below may pay voluntarily.
HMRC usually asks you to pay tax in two instalments — 31 January and 31 July — each being 50% of the previous year's bill as an advance towards the next year.
A common rule of thumb is to save 25–30% of your profit for tax and National Insurance, more if you're a higher-rate taxpayer or have payments on account.
Yes. Many people have both. Your employment is taxed through PAYE, and you report self-employed profit through Self Assessment — the calculator helps estimate the extra tax.
Disclaimer
This calculator provides estimates for guidance only. It is not financial, legal or tax advice. Always check official sources or speak to a qualified professional before making decisions.
Related tools
Income Tax Calculator UK
Work out your income tax bill across the 2026/27 tax bands.
Open calculator →National Insurance Calculator UK
Estimate your employee National Insurance and what your employer pays.
Open calculator →PAYE Salary Calculator UK
Estimate income tax, National Insurance and take-home pay.
Open calculator →