UK Self-Employment Tax Calculator
Calculate your total tax liability as a self-employed sole trader for the 2025/26 or 2024/25 tax year. See your income tax, Class 2 and Class 4 National Insurance, and payments on account.
Total Tax
£8,621.60
Effective rate: 19.16%
Net Income
£36,378.40
After all taxes
Net Profit
£45,000
After expenses
| Item | Amount |
|---|---|
| Gross Income | £50,000 |
| Business Expenses | −£5,000 |
| Net Profit | £45,000 |
| Income Tax | £6,486.00 |
| Class 2 National Insurance | £189.80 |
| Class 4 National Insurance | £1,945.80 |
| Total Tax | £8,621.60 |
| Net Income | £36,378.40 |
Payments on Account
HMRC requires two payments on account: £4,310.80 each, due 31 January and 31 July.
Frequently asked questions
What taxes do self-employed people pay in the UK?
Self-employed individuals in the UK pay income tax on their net profit (after allowable expenses), Class 2 National Insurance (a flat weekly rate of £3.50 in 2025/26 if profits exceed the Small Profits Threshold of £6,845), and Class 4 National Insurance (6% on profits between £12,570–£50,270 and 2% above £50,270).
What are payments on account?
Payments on account are advance payments towards your tax bill. HMRC requires two payments, each equal to half of your previous year's tax bill. The first is due on 31 January (during the tax year) and the second on 31 July (after the tax year ends). Any remaining balance is settled with your Self Assessment return.
What expenses can I deduct as a sole trader?
You can deduct allowable business expenses including office costs, travel, clothing (uniforms), staff costs, stock and materials, financial costs (bank charges, insurance), business premises costs, advertising, and training courses related to your business. The expense must be wholly and exclusively for business purposes.
Sources
Related Calculators
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National Insurance Calculator
Class 1, 2 & 4 NI for employed and self-employed.
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