Last updated: 14 October 2026
Do you need to fill in a tax return?
You need to file a Self Assessment tax return for 2026/27 if you were self-employed with gross income over £1,000, a partner in a partnership, had untaxed income such as rent over £1,000, needed to pay the High Income Child Benefit Charge, had income over £150,000, or had capital gains to report. HMRC may also send you a notice to file, and if it does, you must file even if you think you don’t owe anything. If you’re only employed and taxed through PAYE, you usually don’t need one.
Who needs to file for 2026/27
| Situation | Return needed? |
| Self-employed, gross income over £1,000 | Yes |
| Partner in a business partnership | Yes |
| Rental income over £1,000 (or over £7,500 under Rent a Room) | Yes |
| Taxable income over £150,000 | Yes |
| Untaxed income over £2,500 (e.g. tips, commission) | Yes |
| Savings or dividend income over £10,000 | Yes |
| Taxable capital gains, or disposals over £50,000 | Yes |
| Child Benefit with income over £60,000 and not paying through PAYE | Yes, unless you pay the charge through your tax code |
| Company director | Not automatically, unless you have untaxed income |
| Foreign income | Usually yes |
Who doesn’t need to file
- Employees and pensioners taxed fully through PAYE
- People with small amounts of untaxed income HMRC can collect through their tax code
- Sellers of personal items only
Key deadlines
- Register by 5 October 2027 if you first need to file for 2026/27
- Paper return: 31 October 2027
- Online return and payment: 31 January 2028
Example
Hannah works full-time on a £35,000 salary and lets a flat for £9,600 a year. Her rent isn’t taxed at source, so she must register for Self Assessment and report the rental profit. Her colleague Tom earns £48,000 with no other income; he doesn’t need to file.
Penalties for not filing
If you miss the deadline, there’s an initial £100 penalty, rising after 3, 6 and 12 months. Interest is charged on late tax. If you were sent a notice to file but don’t need to, ask HMRC to withdraw it rather than ignoring it.
Making Tax Digital
From 6 April 2026, sole traders and landlords with qualifying income over £50,000 must use MTD for Income Tax, keeping digital records and sending quarterly updates. The threshold falls to £30,000 from April 2027 and £20,000 from April 2028.
Common mistakes
- Assuming PAYE covers rental or side income
- Missing the 5 October registration deadline
- Ignoring a notice to file
- Not telling HMRC when you stop needing to file
Use HMRC’s checker
HMRC’s online tool asks about your income and tells you whether you need to file. Keep a note of the result.
Telling HMRC you no longer need to file
If your side income stops, tell HMRC before the end of the tax year in which you stop, so it doesn’t send a notice to file. If you’ve already been sent one, you must still file unless HMRC agrees to withdraw it.
Frequently asked questions
Do pensioners need to file?
Only if they have untaxed income HMRC can’t collect through PAYE.
Do I need to file if I’m due a refund?
You can claim through other routes, but filing works too.
Can I deregister?
Yes, tell HMRC once your circumstances change.
Does a director need a return?
Not just for being a director.
Related: how much tax you owe, late filing fines and freelance income while employed.
Talk to Accotax
Want this handled for you? Our team at Accotax can help with tax return registration and filing. See our Self Assessment tax return service service, or contact us for a free, no-obligation quote.
This page is general guidance based on HMRC rules for the 2026/27 tax year, checked against gov.uk on 14 October 2026. It is not personal advice, so speak to an accountant about your own situation.
