You'll usually need to file if…
- HMRC has asked you to. If you get a notice to file, you must send a return or ask HMRC to withdraw the notice.
- You're self-employed (a sole trader) and your trading income was more than £1,000 before expenses — see the trading allowance.
- You're a partner in a business partnership.
- You received rental income above the £1,000 property allowance — see rental income tax.
- You had untaxed income of £2,500 or more, such as tips, commission or foreign income. (Between £1,000 and £2,500 you can usually contact HMRC to have it collected through your tax code instead.)
- You had dividends above £10,000, or above the £500 dividend allowance if HMRC can't collect the tax through your code.
- You had savings interest that isn't covered by your allowances and can't be collected through PAYE.
- You or your partner got Child Benefit and one of you had adjusted net income over £60,000, and you're not paying the High Income Child Benefit Charge through your tax code.
- You sold assets at a gain above the Capital Gains Tax annual exempt amount, and need to report it.
You probably don't need to file if…
- Your only income is wages or a pension taxed through PAYE.
- Your savings interest is within your Personal Savings Allowance.
- Your side income is under £1,000 a year (trading or property allowance).
- Your untaxed income is between £1,000 and £2,500 and HMRC collects it through your tax code.
Even if you don't have to file, you can sometimes choose to — for example to claim tax relief on pension contributions or Gift Aid as a higher-rate taxpayer.
Useful tool
Want a quick yes or no? Answer nine questions in our free checker.
Common situations
| Situation | Usually need a return? | More |
|---|---|---|
| Employee with one job (PAYE only) | No | Employees |
| Sole trader earning £1,000+ | Yes | Self-employed |
| Landlord with rent over £1,000 | Yes (over £2,500), or contact HMRC (£1,000–£2,500) | Landlords |
| Director taking dividends | Often | Company directors |
| CIS subcontractor | Yes — and often due a refund | CIS refunds |
| Selling online occasionally (personal items) | Usually no | Trading allowance |
How to check for certain
HMRC's free online checker on GOV.UK asks a few questions about your income and tells you whether you need to send a return for 2025/26. If it says yes and you've never filed, register for Self Assessment by 5 October 2026.
If you do need to file
- Register (if it's your first time) and get your UTR.
- Collect your documents — P60, invoices, statements.
- Start your return on TaxGo: upload what you have, answer what's missing, review and approve. £79 per return.
- Pay by 31 January — see how to pay.