Self Employed Tax Calculator UK

Quickly calculate how much tax you’ll pay as a sole trader with our Self Employed Tax Calculator UK. Whether you’re freelancing, running a small business, or just starting out, this tool helps you estimate your Income Tax and National Insurance contributions instantly.

No spreadsheets. No confusion. Just fast and accurate results.

What Is Self Employed Tax?

If you’re self-employed in the UK, you’re responsible for paying tax on your profits through the Self Assessment system.

Your total tax bill usually includes:

Income Tax
Class 2 National Insurance
Class 4 National Insurance

Our Self Employed Tax Calculator UK combines all of these into one simple calculation.

How to Use the Self Employed Tax Calculator

Using the calculator is simple:

Enter your annual income
Add your business expenses
Input any other income (if applicable)
Click calculate

You’ll instantly see:

Your taxable profit
Income tax owed
National Insurance contributions
Total tax bill

How Self Employed Tax Is Calculated

Your tax is based on your profit, not total income.

Step 1: Calculate Profit

Profit = Income – Expenses

Step 2: Apply Personal Allowance

You don’t pay tax on income up to £12,570 (current threshold)

Step 3: Apply Income Tax Rates

20% (Basic rate)
40% (Higher rate)
45% (Additional rate)

Step 4: Add National Insurance

Class 2: Flat weekly rate
Class 4: Based on profits

Who Should Use This Tool?

This calculator is perfect for:

Freelancers
Sole traders
Small business owners
Gig economy workers (Uber, Deliveroo, etc.)
Side hustlers earning extra income

Example Calculation

If your annual income is £40,000 and expenses are £10,000:

Profit = £30,000
Taxable income = £17,430 (after allowance)
Estimated tax + NI = Calculated instantly by the tool

Common Mistakes to Avoid

Forgetting to deduct expenses
Not setting aside money for tax
Ignoring National Insurance
Misunderstanding tax bands

Using a Self Employed Tax Calculator UK helps you avoid these costly errors.

FAQs – Self Employed Tax Calculator UK

How much tax do I pay if I’m self-employed?

It depends on your profit. You’ll pay Income Tax and National Insurance based on UK tax bands.

Do I pay tax on total income or profit?

You only pay tax on your profit (income minus allowable expenses).

What expenses can I claim?

Common expenses include office costs, travel, equipment, and business-related bills.

Do I need to file a Self Assessment?

Yes, if you’re self-employed, you must submit a Self Assessment tax return each year.

Is this calculator accurate?

Yes, it provides a reliable estimate based on current UK tax rates, but final figures may vary.