Self-Employed Tax Calculator

Estimate income tax and Class 4 National Insurance on your sole trader profits.

Your result

Total tax and NI£7,131.80
Income tax£5,486.00
Class 4 NI£1,645.80
Profit after tax£32,868.20
Set aside each month£594.32

Updates as you type. Based on 2025/26 UK figures where relevant.

How this is worked out

Income tax is charged on profit above your personal allowance. Class 4 NI is 6% on profits between £12,570 and £50,270 and 2% above.

Tips

  • Check your tax code on every payslip. 1257L is the standard code for 2025/26; anything else deserves a quick look in your HMRC app.
  • Pension contributions and salary sacrifice reduce your taxable pay, which matters most if you're near a band threshold.
  • If your income is between £100,000 and £125,140, you lose personal allowance and face an effective 60% marginal rate. Pension contributions can bring it back.

Guides for this calculator

More tax and pay calculators

Frequently asked questions

How does the self-Employed Tax Calculator work?

Income tax is charged on profit above your personal allowance. Class 4 NI is 6% on profits between £12,570 and £50,270 and 2% above.

When does the UK tax year start?

The UK tax year runs from 6 April to 5 April the following year. Most allowances and bands reset on 6 April.

Where can I check the official rates?

GOV.UK publishes all current income tax, National Insurance and student loan rates. Our figures are based on the tax year shown on each calculator.

Is this calculator a substitute for advice?

No. It gives a clear estimate for common situations. For complex cases such as multiple incomes, benefits in kind or residency questions, speak to an accountant or HMRC.

This calculator gives an estimate for general information. It isn't financial, tax, legal or medical advice. Check official figures on GOV.UK or NHS.uk, or speak to a qualified adviser.