TradesmenSmall BusinessesHow It WorksGet a Free EstimatePricing
BlogFree Tax CalculatorsHelp CentreFAQSupportOur Infrastructure
StripeXeroQuickBooksHMRC (MTD)Meta Lead AdsCloudflareWhatsApp AI
AboutPartner APIContactPortfolioSecurityPrivacy PolicyTerms of Service
A.X.E.L
Free Tool · 2025/26

Self-Employed Tax Calculator

Enter your annual income and expenses to instantly see your income tax, National Insurance, student loan repayments, and take-home pay for the 2025/26 tax year.

Understanding Self-Employed Tax in the UK

As a self-employed tradesman or sole trader in the UK, your tax obligations are different from employees. You're responsible for calculating and paying your own income tax and National Insurance contributions through the Self Assessment system.

Your tax is calculated on your taxable profit — that's your total income minus your allowable business expenses. For 2025/26, the first £12,570 of profit is tax-free (your personal allowance). After that, you pay 20% basic rate on income up to £50,270, 40% higher rate up to £125,140, and 45% additional rate on anything above.

On top of income tax, you also pay National Insurance. Class 2 is a flat £3.45 per week if your profits exceed £12,570. Class 4 is 6% on profits between £12,570 and £50,270, then 2% on profits above £50,270. These are all collected through your annual Self Assessment return, due by 31 January.

This calculator uses the latest 2025/26 HMRC rates to give you an instant estimate of your tax bill. It includes income tax, both classes of National Insurance, and student loan repayments. All calculations run in your browser — nothing is stored or sent anywhere.

Frequently Asked Questions

As a sole trader, you pay income tax on your taxable profit (income minus allowable expenses). You also pay National Insurance — Class 2 (a flat weekly rate) and Class 4 (a percentage of profits). You file these through your annual Self Assessment tax return.
The personal allowance for 2025/26 is £12,570. This is the amount you can earn before paying income tax. If your income exceeds £100,000, your personal allowance reduces by £1 for every £2 over the threshold, disappearing entirely at £125,140.
You can claim for costs that are wholly and exclusively for business purposes: tools and materials, vehicle costs (mileage or actual costs), phone bills, insurance, accountancy fees, workwear, subcontractor costs, and more. Keep receipts for everything.
The tax year runs from 6 April to 5 April. You need to register for Self Assessment by 5 October after your first tax year of trading. Paper returns are due by 31 October, and online returns by 31 January following the tax year end.
Yes. Self-employed workers pay Class 2 NI (£3.45/week in 2025/26 if profits exceed £12,570) and Class 4 NI (6% on profits between £12,570–£50,270, then 2% above that). These are collected through Self Assessment.
You might also find useful
Construction Industry SchemeCIS Tax CalculatorCalculate →Value Added TaxVAT CalculatorCalculate →

Managing your taxes shouldn't be this hard.

Try A.X.E.L — built for tradesmen. Track income, log expenses automatically, and stay on top of your tax bill all year round.

Try A.X.E.L Free →
Let's talk