UK Self-Employment Tax Calculator
Tax Breakdown
Taxable Income: £
Income Tax: £
Class 2 NICs: £
Class 4 NICs: £
Total Tax & NICs: £
How to Use the UK Self-Employment Tax Calculator
A UK Self-Employment Tax Calculator is a tool designed to help sole traders and freelancers in the UK estimate how much tax and National Insurance Contributions (NICs) they may owe to HMRC at the end of the tax year.
What the Calculator Does
Self-employed individuals are responsible for calculating and paying their own taxes, unlike employees who have PAYE (Pay As You Earn) deductions automatically taken from their salaries. This calculator simplifies the process by giving you a clear breakdown of:
- Your taxable income (after allowable business expenses and personal allowance).
- Your income tax liability.
- Your Class 2 NICs.
- Your Class 4 NICs.
- The total amount owed.
This is an estimate only and should be used as a guide—final calculations should always be confirmed with official HMRC resources or an accountant.
How to Use the Calculator
- Enter your annual self-employment income (£) – This is your total revenue before deducting expenses.
- Enter your allowable business expenses (£) – This can include office supplies, travel costs, software subscriptions, or other eligible expenses.
- Click “Calculate Tax” – The calculator will instantly estimate your taxable income, tax owed, and NICs.
- View your tax breakdown – The result box will show:
- Taxable income after allowances
- Income tax owed
- NICs owed (Class 2 & Class 4)
- Total amount to set aside
 
Example
- Income: £30,000
- Expenses: £5,000
- Taxable income: £12,430 (after £12,570 allowance)
- Estimated Tax + NICs = ~ £3,700
This gives you a clear idea of what to budget for when saving for your annual tax bill.
FAQ: UK Self-Employment Tax Calculator
Q1: Does this calculator include personal allowance?
Yes, it deducts the standard personal allowance (£12,570 for 2023/24) before calculating tax.
Q2: Does it work for Scotland?
This calculator uses the UK standard tax bands, not Scottish-specific rates. Scottish taxpayers should be aware of different thresholds.
Q3: What are Class 2 and Class 4 NICs?
- Class 2 NICs are flat-rate weekly contributions if your profits are above the lower earnings threshold.
- Class 4 NICs are percentage-based contributions on profits above certain thresholds.
Q4: Does it include Class 1 NICs?
No, Class 1 applies to employees, not the self-employed.
Q5: Is this calculator HMRC-approved?
No, it’s an educational tool. Always double-check your figures using HMRC’s official calculator or consult an accountant.
Q6: Can I use this for Limited Companies?
No, this is for sole traders / self-employed individuals. Limited companies have different tax rules (corporation tax, salaries, dividends).