Side Hustle Tax Calculator UK 2026/27
Compare the £1,000 trading allowance with actual allowable expenses and estimate how much trading profit could be added to your taxable income. Figures checked 6 October 2026.
Enter your annual figures
Important: this is an educational estimate, not a Self Assessment return. It assumes you are eligible to use the trading allowance and, for the Income Tax estimate, uses the 2026/27 main rates for England, Wales and Northern Ireland. Scottish Income Tax differs. It does not model every adjustment, relief, benefit interaction or National Insurance interaction.
The £1,000 test uses gross trading income
HMRC’s trading allowance is based on eligible gross trading income before expenses. If total relevant trading income is £1,000 or less, full relief may mean you do not need to tell HMRC about it, subject to exceptions. If gross trading income is over £1,000, you may need to tell HMRC and can potentially choose between deducting allowable actual expenses and using partial relief under the trading allowance rules.
You cannot normally deduct both
If you claim the trading allowance instead of actual expenses, HMRC says you cannot also deduct those actual expenses or other allowances from the same income. That is why this calculator shows the two methods side by side rather than subtracting £1,000 and your expenses together.
What about National Insurance?
For 2026/27, Class 4 National Insurance is generally 6% on self-employed profits over £12,570 up to £50,270 and 2% above £50,270. But if you are both employed and self-employed, GOV.UK says the amount can depend on your combined wages and self-employed work. For that reason this side-hustle calculator does not pretend a simple Class 4 figure is exact when PAYE employment is involved. Use our Self-Employed Tax Calculator for a sole-trader-only planning estimate and check HMRC for your circumstances.
Essential side-hustle tax guides
- Side Hustle Tax UK: £1,000 Trading Allowance explained
- When to register for Self Assessment for a side hustle
- Trading allowance vs allowable expenses
- Side hustle tax when you are employed
- Vinted tax UK and Etsy fees & tax UK
Official sources
- GOV.UK: trading and property income allowances
- GOV.UK: self-employed expenses
- GOV.UK: National Insurance
Checked 6 October 2026. General information only, not personalised tax, accounting, legal or financial advice.