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UK · 2026/27

Self-Employed Tax Calculator

Estimate 2026/27 Income Tax and Class 4 National Insurance on UK sole-trader profit. Personal pension input uses relief-at-source assumptions; voluntary Class 2 is excluded.

Last reviewed: 5 August 2026Source: GOV.UK — National Insurance: how much you payUpdated every: tax-year or rule change
Self-Employed Tax Calculator · UKTax & Salary

Results update when you select Calculate.

Example result based on the prefilled values.

Calculation results
ResultValue
Net Profit After Tax & Entered Pension Payment

£27,168.20

Income Tax

£4,486.00

Class 4 NI

£1,345.80

Total Tax + NI

£5,831.80

Effective Tax + NI Rate

16.66%

Continue your plan

Useful next calculations

Related to this calculation

Rates & sources2026/27

2026/27 sole-trader estimate using Income Tax, Class 4 National Insurance and an optional relief-at-source pension payment. Voluntary Class 2 is not added.

Rates used for 2026/27
Band / figureRate
Class 4 main rate6% · £12,570 – £50,270 profit
Class 4 additional rate2% above £50,270
Voluntary Class 2£3.65 a week — excluded

Source: GOV.UK — National Insurance: how much you pay — source checked for 2026/27.

When to use this calculator

  • Before accepting a pay change, bonus, pension contribution, or salary-sacrifice option.
  • When you want to compare employed, self-employed, or dividend-based income scenarios.
  • When you need a simple take-home estimate before running payroll or filing returns.
  • When you are approaching the £100,000 income level and want to understand the personal allowance taper effect.
  • When you are planning a salary sacrifice arrangement and need to see the net pay impact before agreeing terms.

Worked example: £55,000 income, £5,000 expenses

Use these sample inputs as a quick scenario test, then change one variable at a time to compare outcomes.

Worked example: £55,000 income, £5,000 expenses
InputValue
Gross income£55,000
Less expenses£5,000
Taxable profit£50,000
Personal Allowance£12,570
Income tax (£37,430 × 20%)£7,486
Class 4 NI (£37,430 × 6%)£2,246
Total tax + NI£9,732
Net profit£40,268

The effective rate in this simple example is 19.5%. Profit above £50,270 can fall into a 40% Income Tax and 2% Class 4 NI marginal band, subject to allowances and the rest of your tax position.

How to read your results

Net Profit After Tax & Entered Pension Payment

Review this figure alongside your gross income so you can understand the true cost of deductions and plan around any thresholds before the tax year closes. If the figure looks higher than expected, check whether any pension or gift-aid contributions could reduce your taxable income.

Income Tax

Review this figure alongside your gross income so you can understand the true cost of deductions and plan around any thresholds before the tax year closes. If the figure looks higher than expected, check whether any pension or gift-aid contributions could reduce your taxable income.

Class 4 NI

Use this metric to compare scenarios side by side and understand how changes in the key inputs drive the final outcome. If the figure surprises you, isolate one variable at a time and rerun the calculation to identify which assumption is responsible.

Total Tax + NI

Review this figure alongside your gross income so you can understand the true cost of deductions and plan around any thresholds before the tax year closes. If the figure looks higher than expected, check whether any pension or gift-aid contributions could reduce your taxable income.

Effective Tax + NI Rate

Review this figure alongside your gross income so you can understand the true cost of deductions and plan around any thresholds before the tax year closes. If the figure looks higher than expected, check whether any pension or gift-aid contributions could reduce your taxable income.

Method & assumptionsAuthoritative sources

This calculator estimates 2026/27 Income Tax and Class 4 National Insurance for a sole trader in England, Wales or Northern Ireland. Enter trading income and allowable expenses; the model calculates taxable profit before pension contributions, as HMRC does not treat an ordinary personal pension payment as a business expense. A relief-at-source pension payment is grossed up to extend the basic-rate band and reduce adjusted net income, while its net cash cost is shown in the remaining profit figure.

Voluntary Class 2 is deliberately excluded. The calculator does not cover employment income, Scotland, student loans, HICBC, VAT, losses, capital allowances, partnership allocations, basis-period rules or a complete Self Assessment return. Verify the result with HMRC or a qualified accountant before filing or choosing a pension contribution.

Common mistakes

  • !Entering gross income when you really want take-home pay, or vice versa.
  • !Ignoring pension contributions, deductions, or local tax rules that change the result.
  • !Comparing monthly and annual figures without standardising them first.
  • !Overlooking the National Insurance threshold changes that apply mid-year when rates or bands are adjusted in a Budget.
  • !Assuming a salary sacrifice benefit reduces take-home pay by the full gross amount, rather than only the after-tax cost.

What to do next

  • Check the same scenario with related pay or deduction calculators to see the full picture.
  • Keep a copy of the assumptions you used so you can compare next tax year or pay period accurately.
  • Read the related guides below if you are choosing between multiple income or deduction options.
  • If you are self-employed, run the self-employment tax calculator alongside this result to compare the net position against employed income.
  • Check whether increasing your pension contribution by even one or two percent changes the take-home significantly — use the pension calculator next.

Frequently asked

Enter gross trading income, allowable business expenses and any personal pension payment made under relief at source. The calculator estimates 2026/27 Income Tax and Class 4 National Insurance. It treats the pension payment as a net payment that is grossed up for tax-relief and band-extension modelling; it does not deduct it from taxable trading profit.

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