Self Employed Tax Calculator, 2026/27
Once trading profit is known, this calculator applies income tax and Class 4 National Insurance to show what a sole trader actually owes for the year, and a simple percentage to set aside from future income.
The self employed tax calculator runs on the rates and thresholds HMRC has published for the 2026/27 tax year, so the figures you see reflect the position your company is actually filing on rather than a historic set of bands. Change any input and the result recalculates immediately, with no sign-up and nothing sent anywhere.
If you are a director of a UK limited company, use it as a first look before a decision rather than as the decision itself. Uses the 2026/27 personal allowance and income tax bands, applied to trading profit stacked on top of any other income entered. Real company positions bring in other income, reliefs, group structures and prior year adjustments that a single page of inputs cannot see, which is why the workings are written out below under personal & self assessment tax. Read those, then check the numbers against your own accounts, and speak to us if anything looks materially different from what you expected.
Last reviewed 12 September 2026 for the 2026/27 tax year. Reviewed by Waqas Sagar, Member of ICAEW, Fellow of ACCA, Fellow of AAT.
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Result, 2026/27
Total tax and Class 4 NIC due
Income tax on your profit
Class 4 National Insurance
6.0% up to £50,270, 2.0% aboveSuggested percentage to set aside
Illustration only, figures are based on the rates you have selected and the information entered. Please check your own position with us before acting.
Estimates for the 2026/27 tax year using published GOV.UK rates. Switch between 2026/27 and 2025/26 above.
How this is calculated
Sole traders pay income tax on trading profit in exactly the same bands as employees pay on salary: the personal allowance, then 20% basic rate, 40% higher rate and 45% additional rate. If you have other taxable income, such as a part-time job or rental income, this calculator stacks your trading profit on top of it to find the correct marginal rate.
On top of income tax, sole traders pay Class 4 National Insurance on profits above the lower profits limit, at 6.0% up to £50,270 and 2.0% above that, collected through the same self-assessment return rather than through payroll.
The result is a combined figure that shows the true cost of trading profit once both income tax and Class 4 National Insurance are accounted for, which is usually the number sole traders actually need to budget against.
Getting from turnover to this figure
This calculator assumes you already have a net taxable profit figure. If you need to work that out from turnover and expenses, or decide between actual expenses and the trading allowance, use the self-employed profit calculator on this site first.
Losses, capital allowances and pension contributions can all reduce the profit figure used here, so it is worth finalising bookkeeping before relying on the tax figure for budgeting.
Setting money aside
Because tax on self-employment is paid well after the money is earned, often 10 months later through payments on account, many sole traders find it easier to set aside a fixed percentage of income as it comes in, ideally into a separate account, rather than calculating precisely every time.
This calculator's suggested percentage is based on the current year's profit only; it does not include payments on account for the following year, which can roughly double the January cash outflow in some circumstances.
What this means for your company
Treat the result as a planning figure for the 2026/27 tax year. If it changes what you were about to do, take a director's salary, a dividend, a large asset purchase or a filing decision, check it against your own accounts first. We can review the position with you and confirm the tax treatment before you commit.
Frequently asked questions
Do sole traders pay National Insurance the same way as employees?
No. Employees pay Class 1 National Insurance through PAYE, while sole traders pay Class 4 on their profits through self-assessment, along with Class 2 in some cases, which builds state pension entitlement.
Is Class 4 National Insurance included in this figure?
Yes, this calculator adds Class 4 National Insurance to the income tax due, since both are usually paid together as part of the same self-assessment bill.
How much should I set aside from self-employed income?
This varies with profit level, but this calculator shows the effective combined rate for your figures, which is a reasonable starting percentage to set aside as income is earned through the year.
Does this include payments on account?
No, this shows the tax due for the year itself. Once that liability exceeds £1,000, HMRC usually also requires advance payments on account towards next year, covered by the payment on account calculator on this site.
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