Guide
Key deadlines
The UK tax year runs 6 April to 5 April. Most deadlines cluster around 31 January, 31 July, 5 October and 31 October.
Step by step
- 1Note the tax year you're filing for
- 2Register by 5 October if you're new
- 3File paper by 31 October or online by 31 January
- 4Pay balancing payment and first payment on account by 31 January
- 5Pay second payment on account by 31 July
Common mistakes
- Confusing the tax year with the calendar year
- Forgetting the 31 July payment
- Assuming HMRC will remind you
Related guides
Last checked against GOV.UK: 28 October 2026. Tax year 2026/27.
Not affiliated with HMRC. General information, not professional tax advice. Check GOV.UK or speak to a qualified adviser for your situation.