How Far Back Can You Claim Overpaid Tax in the UK?
You can claim a UK tax refund within 4 years of the end of the tax year in which you overpaid. Here are the deadlines for every recent tax year – so you can see whether it is still worth checking.
The 4-year time limit, year by year
Count back from today (August 2026): you can still claim for 2022/23 and every year since, but the window for 2021/22 and earlier has closed.
| Tax year | Claim deadline | Status |
|---|---|---|
| 2021/22 | 5 April 2026 | ❌ Closed |
| 2022/23 | 5 April 2027 | ✅ Open |
| 2023/24 | 5 April 2028 | ✅ Open |
| 2024/25 | 5 April 2029 | ✅ Open |
| 2025/26 | 5 April 2030 | ✅ Open |
| 2026/27 | 5 April 2031 | ✅ Open |
The countdown starts on 5 April when the tax year ends, and runs for exactly 4 years. Claims outside the window are normally rejected.
Does the rule differ by how you claim?
| Route | Time limit |
|---|---|
| P800 (PAYE, automatic) | HMRC issues it after each year; you have 4 years from the end of the tax year |
| Form R40 (income HMRC does not know about) | Within 4 years of the end of the tax year |
| Self Assessment (self-employed) | Amend the return within 4 years of the end of the tax year |
Check whether you may be owed a refund
Quick estimate based on your salary and tax deducted.
Check for a tax refund →FAQs
How far back can I claim overpaid tax?
4 years from the end of the tax year you overpaid. In 2026/27 you can still claim for 2022/23 (deadline 5 April 2027) onwards, but not 2021/22 or earlier.
Can HMRC refund more than 4 years?
No – the limit is fixed. It is only extended in rare cases where HMRC's own error or unreasonable behaviour caused the delay.
Does the 4-year rule apply to self-employed people?
Yes – you can amend a Self Assessment return within 4 years of the end of the relevant tax year.