Self-employed tax calculator for the UK, 2026/27
This self-employed tax calculator for the UK estimates what a sole trader owes HMRC for the tax year 6 April 2026 to 5 April 2027: income tax on your profit, Class 4 National Insurance, Class 2 where it applies, student loan repayments, and the amounts due on 31 January and 31 July once payments on account start. Enter your turnover and expenses, say where you live, and it shows the breakdown, the payment timetable and what you keep.
It handles the questions that come up most: whether to claim expenses or the £1,000 trading allowance, Scottish income tax bands, a salary from a job on top of self-employment, the £100,000 allowance taper, and the £1,000 and 80% tests that decide whether you need payments on account. For PAYE pay alone, use the UK take-home pay calculator.
Rates come from the GOV.UK pages listed under the calculator (checked October 2026). Everything runs in your browser. Results are estimates, not tax advice — check your Self Assessment calculation or ask an accountant.
How to use the UK Self-Employed Tax Calculator
- Enter your turnover (all sales or fees before expenses) and your allowable expenses.
- Leave Deduct on “Whichever is bigger” to let it choose between your expenses and the £1,000 trading allowance, or pick one.
- Choose where you live; Scottish taxpayers get the six Scottish bands.
- If you also have a job, enter the salary and, from your P60, the tax already taken; add any student loan plan.
- If HMRC already set payments on account for 2026/27, enter both payments added together.
- Read the total, the breakdown and the dates to pay, then copy the summary.
UK Self-Employed Tax Calculator features
Income tax on all your income
Profit and salary are taxed together, with the Personal Allowance, the £100,000 taper, and rest-of-UK or Scottish bands.
Class 4 and Class 2 NI
Class 4 at 6% on profit between £12,570 and £50,270 and 2% above; Class 2 treated as paid from £7,105, with voluntary Class 2 below that.
Expenses or trading allowance
Compares your expenses with the £1,000 allowance and uses the bigger deduction, or the one you choose.
Payments on account
Applies the £1,000 and 80% tests and lays out the 31 January and 31 July payments, including the first-year jump.
Student loans
Plans 1, 2, 4 and 5 at 9% and the postgraduate loan at 6%, collected through Self Assessment with the balancing payment.
How self-employed tax is worked out
Profit is turnover minus allowable expenses (or minus the £1,000 trading allowance instead). Profit plus any salary is your total income. The first £12,570 is tax-free; in England, Wales and Northern Ireland the next £37,700 is taxed at 20%, income up to £125,140 at 40% and anything above at 45%. Class 4 NI is charged on profit only: 6% between £12,570 and £50,270, then 2%.
Worked example: £45,000 of sales and £5,000 of expenses give £40,000 profit. Income tax is 20% of £27,430 = £5,486 and Class 4 is 6% of £27,430 = £1,645.80, so the bill is £7,131.80. Because it is over £1,000, HMRC also asks for two payments on account of £3,565.90 towards next year — so 31 January 2028 brings £10,697.70 and 31 July 2028 another £3,565.90.
2026/27 self-employed rates
| Item | 2026/27 | Notes |
|---|---|---|
| Personal Allowance | £12,570 | Falls £1 per £2 over £100,000 |
| Income tax (rest of UK) | 20% / 40% / 45% | Scotland: 19, 20, 21, 42, 45, 48% |
| Class 4 NI | 6% · 2% | £12,570 – £50,270 · above £50,270 |
| Small profits threshold | £7,105 | Class 2 treated as paid at or above it |
| Voluntary Class 2 | £3.65 a week | £189.80 for 52 weeks |
| Trading allowance | £1,000 | Instead of expenses, not as well |
| Payments on account | 50% each | 31 January and 31 July; not needed under £1,000 or if over 80% paid at source |
Payments on account and the first-year shock
Payments on account are advance payments towards next year’s bill, each half of this year’s income tax and Class 4 (less tax already taken at source). The balancing payment on 31 January settles the rest, together with student loan repayments and any Class 2. In your first year you pay the whole bill plus the first advance payment on the same day, so set aside about 150% of a year’s tax. You can ask HMRC to reduce payments on account if profits are falling.
If you price your own work, the freelance rate calculator helps you build tax into your rate, and the mileage log keeps the trip records the simplified mileage rate needs.
UK Self-Employed Tax Calculator FAQ
How much tax do I pay if I am self-employed in the UK?
On £40,000 profit in England in 2026/27, about £7,132: £5,486 income tax and £1,645.80 Class 4 NI. This self-employed tax calculator shows your own figures, including Scotland and a second job.
What National Insurance do self-employed people pay in 2026/27?
Class 4 at 6% on profit between £12,570 and £50,270 and 2% above. Class 2 is not payable: at £7,105 profit or more it is treated as paid, and below that you can pay £3.65 a week voluntarily to protect your State Pension.
Is the calculator different for Scotland?
Income tax uses the six Scottish bands from 19% to 48%. Class 4 NI and student loan repayments are the same everywhere in the UK.
Should I claim expenses or the £1,000 trading allowance?
Whichever is bigger. If your expenses are under £1,000, the allowance gives a larger deduction; you cannot claim both against the same income.
When do I have to pay?
The 2026/27 return and balancing payment are due by 31 January 2028, with payments on account for 2027/28 on 31 January and 31 July 2028.
Is this tax advice?
No. It is an estimate from published HMRC rates. Your Self Assessment calculation is what counts.