Side income & self-employed
What will you actually keep from your profit?
Income Tax and Class 4 National Insurance, worked out together.
Self-employed tax calculator
Income Tax and Class 4 National Insurance on your profit — 2026/27 rates
Income minus allowable business expenses.
Income Tax
£4,486
Class 4 National Insurance
£1,346
Take-home profit
£29,168
Estimate only — doesn't account for pension contributions, Marriage Allowance, student loans, or other adjustments to your tax bill. Payments on account (advance payments toward next year's tax bill) aren't included here either — factor those in separately when budgeting for your Self Assessment bill.
As a sole trader, you pay Income Tax on your profit (income minus allowable business expenses) using the same bands as employees, plus Class 4 National Insurance — 6% on profit between £12,570 and £50,270, and 2% above that. Unlike employees, there's no employer NI on your own income. Class 2 NI was abolished in April 2024 — if your profit is above £7,105, you still get a State Pension qualifying year automatically, with nothing extra to pay.
Frequently asked questions
What National Insurance do self-employed people pay?
Class 4 National Insurance — 6% on profits between £12,570 and £50,270, and 2% above that, for 2026/27. Class 2 NI was abolished in April 2024.
Do I pay Income Tax on my self-employed profit or turnover?
Profit — your income minus allowable business expenses, taxed using the same bands as employees.