Self-Employed Tax Calculator
Estimate your Self Assessment bill as a sole trader or freelancer, and how much to put aside each month so January is not a shock.
Your business
Use whichever is higher. Allowable expenses include materials, travel, phone, insurance and accountancy fees.
Payments on account: because your bill is over £1,000, HMRC will usually ask you to pay half of next year’s bill in advance, by 31 January and 31 July, on top of this bill.
2026/27 rates for the self-employed
| Profit | Income Tax | Class 4 NI |
|---|---|---|
| Up to £12,570 | 0% | 0% |
| £12,571 to £50,270 | 20% | 6% |
| £50,271 to £125,140 | 40% | 2% |
| Over £125,140 | 45% | 2% |
Worked example: £35,000 profit
Income Tax is 20% of (£35,000 − £12,570) = £4,486. Class 4 NI is 6% of the same £22,430 = £1,345.80. Your total bill is £5,831.80, so you keep £29,168.20, and should put aside about £486 a month.
Payments on account
If your bill is more than £1,000, HMRC usually asks you to pay towards next year’s bill in two instalments of 50%, on 31 January and 31 July. In your first year this can mean paying 150% of a year’s bill in one January, so plan ahead.
Also employed? Check your job’s pay with the take-home pay calculator.
Estimate for guidance. It does not include capital allowances, losses, Gift Aid or pension contributions. Check your figures with HMRC or an accountant.
Guide: payments on account explained, with examples
Guide: sole trader vs limited company
Sources
Figures are checked against these official sources. Last reviewed 7 November 2026.
Common questions
How much tax do I pay when self-employed?
You pay Income Tax on your profit above the £12,570 personal allowance (20% up to £50,270, 40% above), plus Class 4 National Insurance at 6% on profits between £12,570 and £50,270 and 2% above that.
Do I still pay Class 2 National Insurance?
No. Since April 2024 Class 2 has not been compulsory. If your profits are above the small profits threshold (£7,105 in 2026/27) you get National Insurance credits automatically. Below that, you can choose to pay voluntary Class 2 at £3.65 a week to protect your State Pension.
What is the £1,000 trading allowance?
If your business income is small, you can deduct a flat £1,000 instead of your actual expenses. If your turnover is under £1,000 you do not need to tell HMRC at all. Use actual expenses if they are higher. The Autumn Budget 2026 raises the allowance to £3,000 from 6 April 2027.
When do I pay my Self Assessment bill?
The deadline for online returns and payment is 31 January after the tax year ends. For 2026/27 that is 31 January 2028. If your bill is over £1,000 you will usually also make payments on account in January and July.
How much should I save for tax?
A simple rule is to put aside 25 to 30% of your profit if you are a basic-rate taxpayer. This calculator shows the exact monthly figure for your profit.