UK · Self-employment 2026–27

Sole trader tax calculator.

Turn turnover and expenses into profit, then estimate Income Tax and Class 4 National Insurance, with Class 2 status and the trading allowance compared.

Rates as of 30 September 2026 for tax year 6 April 2026 to 5 April 2027, checked against GOV.UK. England, Wales and Northern Ireland only; Scottish income tax bands differ.

Your year

Estimate

Enter turnover to see the estimate.

Worked example

Turnover £50,000 with £10,000 expenses gives £40,000 profit. Personal Allowance £12,570 leaves £27,430 taxable at 20% = £5,486. Class 4 is 6% of (£40,000 − £12,570) = £1,645.80. Total £7,131.80, leaving £32,868.20. Class 2 is treated as paid because profit is over £7,105.

Formula notes

Profit = turnover − expenses, or turnover − £1,000 if you use the trading allowance (you cannot use both).
Income Tax: Personal Allowance £12,570, reduced by £1 for every £2 of income over £100,000 (nil at £125,140). Then 20% on the first £37,700 of taxable income, 40% up to £125,140, 45% above. Source: GOV.UK Income Tax rates.
Class 4: 6% on profits £12,570 to £50,270, 2% above. Class 2: £3.65 a week, treated as paid at profits of £7,105 or more, otherwise voluntary. Source: GOV.UK self-employed National Insurance rates.
Trading allowance: first £1,000 of trading income. Source: GOV.UK trading and property allowances.

Not modelled: other income, pension relief, student loans, payments on account, Scottish bands, capital allowances rules, losses and the high-income child benefit charge. This is a planning estimate, not tax advice; HMRC’s calculation is authoritative. Assumption: the same profit figure is used for Income Tax and Class 4.

FAQ

Do I pay Class 2 as a sole trader?

Not if profits are £7,105 or more in 2026–27, as it is treated as paid. Below that, voluntary Class 2 is £3.65 a week.

Allowance or expenses?

The allowance wins when real expenses are under £1,000; the result shows which is lower for you.

Does this cover Scotland?

No. Scottish residents use different Income Tax bands; Class 4 is the same.