2026/27 tax year · England, Wales & NI
Self-Employed Tax Calculator UK
A free, no-signup self-employed tax calculator for the UK. Estimate your Income Tax and Class 4 National Insurance for 2026/27 — and see the monthly amount to set aside so January never stings.
Work out your 2026/27 tax bill — and what to set aside.
Enter your income and expenses. We'll estimate your Income Tax and Class 4 National Insurance, then split the bill into a monthly amount to put by.
Rates used · 2026/27
- Personal allowance (tax-free) £12,570
- Income Tax bands 20% · 40% · 45%
- Class 4 National Insurance 6% then 2%
towards your 2026/27 Self Assessment bill
- Total tax bill
- £7,652
- Your take-home
- £34,348
- Effective tax rate
- 18.2%
Breakdown
This is an estimate. My Tax Season Prep Kit tracks your set-aside all year so the January bill never surprises you →
Estimate for planning only — not financial or tax advice. Covers England, Wales & Northern Ireland for the 2026/27 tax year (Scotland has different income tax bands). Excludes student loan repayments, pension contributions and other income. Always check gov.uk or an accountant for exact figures.
Self-employed tax FAQs
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How much should I set aside for tax when self-employed?
- A common rule of thumb is 25–30% of your profit, but the right figure depends on your income. This calculator works out a precise monthly amount from the 2026/27 Income Tax and Class 4 National Insurance bands, so you can move it to a separate savings pot each month.
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When is the Self Assessment deadline?
- Online tax returns and payment are due by 31 January after the tax year ends. For the 2026/27 tax year (which ends 5 April 2027) that means 31 January 2028. If you file on paper, the deadline is earlier — 31 October.
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Do I pay National Insurance when self-employed?
- Yes — Class 4 National Insurance at 6% on profits between £12,570 and £50,270, then 2% on profits above £50,270. Class 2 NI was abolished from April 2024, so it is no longer charged.
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What are Payments on Account?
- If your tax bill is over £1,000, HMRC also asks for a 50% advance toward next year's tax, due 31 January and 31 July. In your first year that means your January payment can be 150% of the bill — worth planning for so it doesn't catch you out.