Self-employed tax calculator
Enter your expected profit for the tax year. The calculator applies the personal allowance, income tax bands and Class 4 National Insurance, and shows what to set aside.
Tax and National Insurance for 2026/27
£8,432
Set aside about 19% of profit. Take-home of £36,568, around £3,047 a month.
- Personal allowance
- £12,570
- Taxable profit
- £32,430
- Basic rate at 20%on £32,430
- £6,486
- Income tax
- £6,486
- Class 4 NI at 6% and 2%
- £1,946
- Total to pay through Self Assessment
- £8,432
- Take-home
- £36,568
If this is your first year of Self Assessment, expect to pay around £12,648 by 31 January: this year's bill plus a first payment on account of £4,216 towards next year, with another £4,216 due on 31 July.
Figures used, 2026/27
- Personal allowance £12,570, tapered above £100,000
- Income tax 20%, 40% and 45%
- Class 4 NI 6% from £12,570 to £50,270, 2% above
- Class 2 NI treated as paid; no student loan, pension or other income
England, Wales and Northern Ireland. Rates reviewed . An estimate, not advice: your own position may differ.
How the calculator works
Sole traders and partners pay income tax on their trading profit, which is sales less allowable business expenses. The first 12,570 pounds is covered by the personal allowance. Profit above that is taxed at 20% up to 50,270 pounds, 40% up to 125,140 pounds and 45% beyond. Above 100,000 pounds the allowance tapers away at 1 pound for every 2 pounds of income.
Class 4 National Insurance is charged on the same profit at 6% between 12,570 and 50,270 pounds and 2% above. Class 2 contributions are no longer compulsory: anyone with profits above the small profits threshold is treated as having paid them, which protects State Pension entitlement.
Tax and National Insurance are paid through Self Assessment by 31 January following the tax year, together with a first payment on account of half the next year's estimated bill. A second payment on account falls due on 31 July. The calculator shows a suggested percentage of profit to set aside so the January bill is not a surprise.
On 2026/27 rates a limited company no longer saves tax if you take all the profit out. With 40,000 pounds of profit a sole trader keeps about 32,900 pounds; a director drawing a 12,570 pound salary and the rest as dividends keeps about 31,600. A company can still come out ahead if you leave profit in the business, pay into a pension through the company, or need limited liability. Compare with the limited company tax calculator.
Frequently asked questions
Nothing on the first 12,570 pounds of profit. Above that, income tax at 20%, 40% or 45% depending on the band, plus Class 4 National Insurance at 6% on profit between 12,570 and 50,270 pounds and 2% above. Enter your profit above to see the figures.
Not compulsorily. Since April 2024 self-employed people with profits above the small profits threshold are treated as having paid Class 2, so their State Pension record is protected. Those with lower profits can pay it voluntarily.
Advance payments towards next year's tax bill, each equal to half of this year's liability, due on 31 January and 31 July. They apply once your Self Assessment bill is over 1,000 pounds and less than 80% of your tax is collected at source. The first year can therefore feel like paying one and a half years of tax at once.
As a rule of thumb, 20 to 30% of profit for basic rate taxpayers and 40 to 45% once you are into the higher rate band. The calculator shows your actual effective rate, which is the most reliable figure to use.
Not if you draw all the profit out. On 2026/27 rates a sole trader keeps more than a director taking salary and dividends at every profit level from 30,000 to 150,000 pounds, because Corporation Tax comes first and dividend tax has risen. A company can still win if you leave profit in it, make employer pension contributions, or want limited liability. We model both with your figures.
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