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Start filing →Most people in the UK pay all their tax through PAYE — deducted automatically by their employer. But if you have any income outside of that system, you may need to declare it yourself through a Self Assessment tax return. Here is a complete guide to who needs to file.
You Must File Self Assessment If Any of These Apply
| Your situation | Threshold / condition |
|---|---|
| Self-employed | Gross income over £1,000 in the tax year |
| Company director | Must file regardless of income level |
| Rental income | Gross rental income over £1,000 |
| High earner | Total income over £100,000 |
| Child Benefit clawback | Income over £60,000 and you or partner claimed Child Benefit |
| Untaxed income | Other income over £2,500 (freelance, tips, commission) |
| Capital gains | Gains exceeding the annual exempt amount |
| Foreign income | Any foreign income that is taxable in the UK |
| Dividends | Dividends above the dividend allowance (£500 in 2024/25) |
| HMRC asks you to | If HMRC sends you a notice to file, you must |
You Probably Do NOT Need to File If
- All your income is from employment taxed through PAYE
- Your self-employed or side income is under £1,000 (covered by trading allowance)
- Your only other income is savings interest below the personal savings allowance
- HMRC has confirmed in writing you do not need to file
Common Situations That Often Catch People Out
How to Register for Self Assessment
Register online with HMRC
Go to HMRC's Self Assessment registration page. You'll need your National Insurance number and personal details.
Receive your UTR
HMRC sends your Unique Taxpayer Reference by post within 10 working days. Keep this safe — you'll need it every year.
Set up your Government Gateway account
You'll also need a Government Gateway user ID and password to file online. Set this up at the same time as registering.
File your first return
Once registered, use SubmitFox to complete and submit your return. Start for free — pay only when you're ready to submit.
Need to file? SubmitFox makes it simple
Start your return for free — you only pay when you're ready to submit.
Start your return for free — you only pay when you're ready to submit. Submits directly to HMRC.
Common Questions
Usually no. If your only income is employment taxed through PAYE and you have no other income sources, you do not need to file. However, if your employment income exceeds £100,000, or you also have side income, rental income, or dividends, you do need to file.
Yes, if your self-employed gross income exceeds £1,000 in a tax year. Even if you made a loss after expenses, you should still file to register the loss with HMRC, which can be carried forward against future profits.
Yes. Once HMRC has issued a notice to file a Self Assessment return, you must file it even if you have no income to declare. Failing to file after receiving a notice results in automatic penalties.
Yes, if you meet any of the filing triggers (self-employment, directorship, rental income, etc.). You may not owe any tax if your income is below £12,570, but you still need to file the return to confirm this to HMRC.
If your circumstances continue (self-employment, rental income, etc.) then yes, you need to file every year. HMRC will send you a filing notice each year. If your circumstances change and you no longer need to file, you must formally deregister with HMRC.