Free UK sole trader tax calculator 2026/27
An estimate of what a self-employed sole trader owes for the tax year 6 April 2026 to 5 April 2027: Income Tax, Class 4 National Insurance, whether the £1,000 trading allowance beats your expenses, the 31 January balancing payment, payments on account, and whether Making Tax Digital quarterly updates apply to you. Nothing you type leaves this page.
Your 2026/27 estimate
| Deducted from income | |
|---|---|
| Taxable trading profit | |
| Total taxable income | |
| Personal Allowance (after any taper) | |
| Income Tax | |
| Class 4 National Insurance | |
| Class 2 National Insurance (voluntary) | |
| Total for the year, less PAYE already paid | |
| Balancing payment due 31 January 2028 | |
| Payments on account for 2027/28 | |
| Making Tax Digital |
Estimate only, from the 2026/27 rates on gov.uk for England, Wales and Northern Ireland (Scottish Income Tax bands differ). It leaves out student loan repayments, savings and dividend income, pension and Gift Aid relief, Marriage Allowance, losses and the High Income Child Benefit Charge. HMRC's own calculation is the one you pay.
Keep the records that produce these numbers
The UK Sole Trader Tax Workbook 2026/27 is the spreadsheet behind this estimate: income, expense and mileage logs that fill in the SA103 boxes and the Making Tax Digital quarters, with the same tax estimate updating as you go. £6.99, one .xlsx, on Etsy, Payhip or this site.
The 2026/27 rates used
| Personal Allowance | |
|---|---|
| Basic rate | |
| Higher rate | |
| Additional rate | |
| Class 4 National Insurance | |
| Class 2 National Insurance | |
| Trading allowance | £1,000, instead of expenses, when it gives the lower profit |
| Payments on account | Two, when the year's tax and Class 4 are over £1,000 and under 80% was paid at source |
| Making Tax Digital for Income Tax | Turnover £50,000+ from April 2026, £30,000+ from April 2027, £20,000+ from April 2028 |
How the estimate works
- Trading allowance or expenses. HMRC lets a sole trader deduct £1,000 instead of actual expenses; the estimate picks whichever leaves the lower profit, as the workbook does.
- Income Tax is charged on your trading profit plus other taxable income after the Personal Allowance, which tapers away above £100,000.
- Class 4 National Insurance is charged on trading profit alone. Class 2 is treated as paid for profits above the small profits threshold; below it you can pay voluntarily.
- Payments on account are two advance payments towards next year, each half of this year's tax and Class 4, when that is over £1,000 and less than 80% was deducted at source.
- Rates read from gov.uk in October 2026. Made with the help of AI tools; the arithmetic is the workbook's, tested against a hand-worked year.