File and pay your Self Assessment online by 11:59pm on 31 January. If you are new to Self Assessment, or you skipped a year, tell HMRC by 5 October. Missed that date? Register now. This page is general information, not tax advice.
The route, stop by stop
01Do you need a return?
Sole traders over £1,000, partners, and many others must send a Self Assessment return. Check if you are in.
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03Register with HMRC
Tell HMRC you need a return. You get a Unique Taxpayer Reference to file online.
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04Gather your figures
Income, expenses, dividends and anything else the return asks for. Keep your records to hand.
05File online by 31 January
Submit your online return by 11:59pm on 31 January. Paper returns have an earlier date.
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07Late filing costs
Miss the online deadline and you get a late filing penalty. Paying late brings its own penalty.
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08Return and payment done
Keep your submission receipt and bank proof. Next year starts again on 6 April.
Who needs a return
You must send a return if, for example, you were a sole trader and earned more than £1,000 before expenses, or you were a partner in a partnership. GOV.UK lists the full set of cases.
The two dates that matter
5 October is the date to tell HMRC you need a return when you have not sent one before, or you skipped a year. 31 January is the online filing and payment deadline for the tax year that ended the previous 5 April.
Missed 5 October?
Register now. The filing and payment deadline is still 31 January, and waiting only shortens the time you have left.
Common questions
When do I file online?
By 11:59pm on 31 January.
When do I pay?
By 11:59pm on 31 January, the same day as the online return.
What if I missed 5 October?
Register now. Do not wait for the next year.
Is this tax advice?
No. It is general information from official pages checked on 9 November 2026. Rules change, so check the sources before you act.
Where the rules come from
- GOV.UK: Self Assessment tax returns: Deadlines checked 9 November 2026
- GOV.UK: Check how to register for Self Assessment checked 9 November 2026
- GOV.UK: Self Assessment tax returns: Who must send a tax return checked 9 November 2026
This map is general information, not personal advice. Rules and rates change, so check the sources before you act. If your situation is tricky, talk to your accountant.
