UK Tax Year Dates 2026: Key Deadlines for Self-Employed
UK Tax Year Dates
The UK tax year runs from 6 April to 5 April the following year.
- 2025/26 tax year: 6 April 2025 - 5 April 2026
- 2026/27 tax year: 6 April 2026 - 5 April 2027
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Key Deadlines for 2025/26 Tax Year
| Date | Deadline |
|---|---|
| 5 October 2026 | Register for Self-Assessment (if new) |
| 31 October 2026 | Paper tax return deadline |
| 31 January 2027 | Online tax return + payment deadline |
| 31 July 2027 | Second payment on account |
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Start Free Trial →Frequently Asked Questions
When does the UK tax year start?
The UK tax year runs from 6 April to 5 April the following year.
When is the Self-Assessment deadline?
Paper returns: 31 October. Online returns: 31 January. Payment deadline: 31 January.
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