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Self-employed tax calculator

Estimate Income Tax and Class 4 National Insurance on your self-employed profit for 2026 to 2027, with any CIS already deducted taken off. Uses GOV.UK rates for England, Wales and Northern Ireland; runs in your browser and nothing is stored.

How the calculator works

Profit is your self-employed income minus allowable expenses, or minus the £1,000 trading allowance if you use that instead (you can't claim both; GOV.UK). For 2026 to 2027 in England, Wales and Northern Ireland, the Personal Allowance is £12,570, basic rate 20% to £50,270, higher rate 40% to £125,140 and additional rate 45% above. The allowance falls by £1 for every £2 of income over £100,000 (GOV.UK). Scotland has different Income Tax bands, so this calculator isn't right for Scottish taxpayers.

Class 4 National Insurance is 6% on profits between £12,570 and £50,270 and 2% above. If your profits are £7,105 or more, Class 2 is treated as paid, so there's nothing extra to pay; below that you can choose to pay voluntary Class 2 at £3.65 a week (GOV.UK). If you have a salary too, the calculator taxes your salary first and shows the extra tax your profit adds.

CIS subcontractors

If contractors deduct CIS from your payments, that's an advance towards your tax and NI. Enter the total deducted to see what's left to pay or the likely refund. Work out a single deduction with the CIS calculator, and read CIS tax refunds explained.

Keep your records in order with FreeAgent, Xero or Zoho Books, and check whether Making Tax Digital applies to you. Setting your prices? Use the day-rate calculator.

An estimate based on GOV.UK rates checked 15 October 2026, not tax advice. Your Self Assessment calculation may differ.

Questions

How much tax does a self-employed person pay in 2026 to 2027?

Income Tax at 20%, 40% or 45% on profit above the £12,570 Personal Allowance, plus Class 4 National Insurance at 6% between £12,570 and £50,270 and 2% above, in England, Wales and Northern Ireland.

Do I still pay Class 2 National Insurance?

Not if your profits are £7,105 or more: it's treated as paid. Below that you can pay voluntary Class 2 at £3.65 a week to protect your record.

Can I use the trading allowance and claim expenses?

No. You use one or the other; the £1,000 trading allowance only helps if your expenses are less than £1,000.

How much should I put aside for tax?

Run your figures above: it shows a monthly amount. Remember that payments on account can mean paying part of next year's bill in advance.