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Tax & money

UK Self-Employed Tax Calculator (2026/27)

Work out income tax and Class 4 National Insurance on your self-employed profit for the 2026/27 tax year, and see what to set aside.

Set aside per year
Per quarter
Share of your profit
Income tax
National Insurance (Class 4)

England, Wales and Northern Ireland rates for 2026/27. Excludes Scottish rates, student loans, dividends, VAT and payments on account. Amounts are in pounds sterling.

How this estimate works

What are the Class 4 National Insurance rates for 2026/27?

6% on profits between £12,570 and £50,270, and 2% above that. This is on top of income tax; Class 2 National Insurance is not included in this calculator.

When do I pay my Self Assessment bill?

The balance for the tax year is due by 31 January. If HMRC asks for payments on account, they are due by 31 January and 31 July, each usually half of the previous year’s bill.

Is this tax advice?

No. It is an estimate for planning purposes only. An accountant can tell you exactly what you owe and confirm your payment dates.