Self-employed tax calculator (UK, 2026/27)
Estimate your income tax and National Insurance, and how much to set aside each month.
An estimate only, for 2026/27 in England, Wales and Northern Ireland (Scottish rates differ). It ignores student loans, pension contributions, Gift Aid, the trading allowance and any other reliefs. Rates and thresholds can change, so check GOV.UK or ask an accountant. Nothing you enter is sent anywhere.
How to use this estimate
Enter your profit, which is your income minus allowable expenses. The result shows roughly how much to set aside for tax and National Insurance. Setting aside a fixed percentage of every payment is the easiest way to avoid a nasty January bill. See our complete Self Assessment guide, the deadlines checklist and the list of allowable expenses.
Keep your profit figure accurate
A calculator is only as good as the profit you give it. Accounting software keeps your income and expenses up to date, so your profit is always a report away. See AvrioBooks for sole traders.
Frequently asked questions
How is self-employed tax calculated?
You pay income tax on your taxable profit above your personal allowance, plus Class 4 National Insurance on profits above £12,570. This calculator estimates both for 2026/27 in England, Wales and Northern Ireland.
What are the 2026/27 rates used here?
Personal allowance £12,570 (reduced above £100,000), 20% basic rate up to £50,270, 40% higher rate up to £125,140, 45% above. Class 4 NI is 6% between £12,570 and £50,270 and 2% above.
Does this include Scottish tax rates?
No. Scotland has different income tax bands, so the result will not be accurate for Scottish taxpayers.
Does it include payments on account?
No. It shows the total for the year. Payments on account spread your bill across 31 January and 31 July.
Know your profit all year, not just at tax time
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