Self Assessment & Personal Tax
Self Assessment deadlines and key dates (2025/26)
Register by 5 Oct 2026, paper return 31 Oct 2026, online + payment 31 Jan 2027, second payment on account 31 Jul 2027.
Self Assessment 2025/26 deadlines: - **5 October 2026** — register if it is your first time. - **31 October 2026 (midnight)** — paper return deadline. - **31 January 2027 (midnight)** — online return + balancing payment + first payment on account for 2026/27. - **31 July 2027** — second payment on account. Filing early gives you more time to budget for the January payment without changing the payment date itself. **Read the full guide at [rraccountants.uk/self-assessment-deadlines](https://rraccountants.uk/self-assessment-deadlines).**
Resources
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