Calculators › Do I Need to File a Tax Return?
Do I Need to File a Self Assessment Tax Return?
Tick everything that applies to you and get an instant answer on whether you probably need to file a Self Assessment tax return.
Tax year 2025/26 · Last reviewed 20 October 2026 · Prepared by the accountants at Self Assessment Tax Return Accountants (a trading style of Accotax). About us
You usually need a Self Assessment tax return if you are self-employed with gross income over £1,000, have rental income over £2,500 (or £1,000 with other costs), are a company director, have untaxed income or gains, or earn over £100,000. The online deadline for the 2025/26 tax year is 31 January 2027. If you are new to Self Assessment you must register with HMRC by 5 October after the end of the tax year.
Who has to file?
You usually need to file if you are self-employed above the threshold, receive rental income, are a company director, earn over £100,000, owe the High Income Child Benefit Charge, have untaxed income, have capital gains or foreign income, or are a partner in a partnership. HMRC can also send you a notice to file, and then you must.
Deadlines
If you are new to Self Assessment you must register with HMRC by 5 October after the end of the tax year. The online return and payment are due by 31 January.
Worked examples
Examples: a freelancer with £8,000 of self-employed income must file. An employee whose only extra income is £500 of bank interest usually does not. A landlord with £3,000 of rent must file. Someone who received Child Benefit and earns over £60,000 must file to pay the High Income Child Benefit Charge.
Common mistakes
- Assuming PAYE means you never need to file.
- Ignoring rental, dividend or foreign income.
- Missing the 5 October registration deadline when starting self-employment.
Related services and guides
- Self Assessment for sole traders
- Self Assessment for landlords
- Self Assessment for high earners
- Self Assessment tax return cost
- Latest guides
Official sources
- Check if you need to file a tax return (GOV.UK)
- Register for Self Assessment (GOV.UK)
- Self Assessment deadlines (GOV.UK)
Frequently asked questions
What if I am not sure?
Use the checker, and if you are unsure, ask an accountant to confirm. It is cheaper than a penalty.
Do I need to file if I only have a job?
Not usually, if your tax is fully collected through PAYE and none of the other triggers apply.
Do I have to register as self-employed?
If your self-employed income is over the trading allowance in a tax year, you normally need to register and file.
What happens if I should have filed and did not?
You may owe tax, penalties and interest. Contact HMRC or an accountant as soon as possible.
Can I file even if I do not have to?
Yes, for example to claim a refund or relief, you can file voluntarily.
