What is the Self Assessment tax return deadline for 2024/25 in the UK?
For the 2024/25 tax year (6 April 2024 to 5 April 2025), the key deadlines are: - Paper return: 31 October 2025 - Online return: 31 January 2026 - Tax payment (any balance owed): 31 January 2026 - Payments on Account (first payment): 31 January 2026 - Payments on Account (second payment): 31 July 2026 If you miss the 31 January 2026 deadline, HMRC charges an automatic £100 penalty even if no tax is owed. Additional penalties apply after 3 months (daily £10 penalties), 6 months (5% of tax or £300), and 12 months. Register for Self Assessment by 5 October 2025 if you've not filed before. You receive your Unique Taxpayer Reference (UTR) after registering.
- Online return deadline: 31 January 2026 for 2024/25 tax year
- Paper return deadline: 31 October 2025 (earlier)
- Tax payment due: 31 January 2026
- Late filing penalty: automatic £100 even if no tax is owed
- Registration for new self-employed: by 5 October 2025