Paper Self Assessment tax return deadline: 31 October
A paper tax return for the last tax year (6 April to 5 April) must reach HMRC by 11:59pm on 31 October. If you file online, you have until 31 January instead.
- Deadline
- Every year by 31 October
- Last checked
- Checked against the official source: 21 October 2026
What if you miss the deadline? A late return gets an initial £100 penalty, even if you have no tax to pay. If you have not posted it yet, you can still file online by 31 January without a penalty.
You can send your Self Assessment tax return on paper or online. The paper deadline is earlier: your return must reach HMRC by 11:59pm on 31 October after the end of the tax year. Most people file online, which gives you three more months.
How to do it
- Decide whether to file on paper or online. Online filing has a later deadline and calculates your tax for you.
- If you file on paper, get the SA100 form and any extra pages you need from GOV.UK.
- Fill in your income, expenses and any reliefs for the tax year that ended on 5 April.
- Post it early so it reaches HMRC by 31 October, and keep a copy.
Common questions
Is 31 October the deadline for all tax returns?
Only for paper returns. Online returns are due by 11:59pm on 31 January.
Is 31 October also the payment deadline?
No. You pay your tax by 31 January, however you file.
What is the penalty for a late paper return?
HMRC charges an initial £100 penalty. More penalties follow after 3, 6 and 12 months.
Official source: gov.uk (opens in a new tab)
Check whether this applies to you and set a reminderThis information is not legal or tax advice.