UK self-employed tax calculator (2026-27)
For 2026-27 you pay Income Tax at 20%, 40% and 45% on income above the £12,570 Personal Allowance, and Class 4 National Insurance at 6% on profits from £12,570 to £50,270 and 2% above. The bands are those for England, Wales and Northern Ireland.
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Informational estimate, not tax advice. SuperBooks does not prepare or file tax forms.
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The formula
Personal Allowance = £12,570, less £1 for every £2 of income over £100,000. Income Tax = 20% on the first £37,700 of taxable income, 40% up to £125,140 and 45% above. Class 4 = 6% of profit between £12,570 and £50,270 plus 2% of profit above £50,270. The taper uses total income as entered; pension contributions and Gift Aid, which reduce adjusted net income, are not included.
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curl "https://app.superbooks.io/api/tools/uk-self-employed-tax?profit=45000"Questions
- What are the Income Tax rates for 2026-27?
- The Personal Allowance is £12,570. Above it, the basic rate of 20% applies to income up to £50,270, the higher rate of 40% to £125,140 and the additional rate of 45% above that. The allowance goes down by £1 for every £2 of adjusted net income over £100,000. Bands are different in Scotland, which this calculator does not cover.
- How much National Insurance does a self-employed person pay in 2026-27?
- Class 4 at 6% on profits between £12,570 and £50,270 and 2% on profits above. Class 2 is £3.65 a week for 2026-27; with profits of £7,105 or more it is treated as paid, so it costs you nothing.
- When do I pay it?
- Through Self Assessment: the online return and the balance are due by 31 January after the tax year, and payments on account, each half of last year's bill, by 31 January and 31 July.