Answers · UK 2025/26

Is there a deadline to claim Marriage Allowance?

There is no deadline to START a Marriage Allowance claim going forward -- once approved it continues automatically each year until cancelled. But BACKDATED claims for previous tax years are time-limited: you generally have four years from the end of a tax year to claim Marriage Allowance for that year, so unclaimed years become permanently lost once the four-year window closes.

Last updated: 1 July 2026Last reviewed: 1 July 2026How we verify

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Marriage Allowance lets one spouse or civil partner (who does not use all of their Personal Allowance, typically because they earn below it) transfer 10% of their allowance to a partner who is a basic-rate taxpayer, reducing the recipient's tax bill by up to £252 a year at current rates. **No deadline for a forward-looking claim** If you want to start claiming Marriage Allowance for the current and future tax years, there is no cut-off date -- you can apply at any point during the tax year (or after it ends) and, once approved, HMRC automatically continues the transfer each subsequent year without you needing to reapply, unless your circumstances change (for example your income rises into higher-rate tax, or you divorce or separate). **The four-year backdating limit** What DOES have a firm deadline is backdating a claim to earlier tax years you did not previously claim for. HMRC generally allows Marriage Allowance to be backdated up to four tax years, provided both partners were eligible in each of those years. Because the ordinary Self Assessment/claims time limit is four years from the end of the relevant tax year, once that four-year window passes for a particular year, that year's Marriage Allowance is permanently lost -- you cannot claim it retrospectively beyond four years, even if you were eligible the whole time and simply never applied. **Worked example** In July 2026, a couple realises they have been eligible for Marriage Allowance since the 2021/22 tax year but never claimed it. Applying now, in 2026/27, they can backdate their claim to cover 2022/23, 2023/24, 2024/25 and 2025/26 (four earlier tax years still within the time limit) plus the current 2026/27 year -- but 2021/22 has already fallen outside the four-year backdating window and cannot be claimed, representing a permanently lost £252 or so of tax saving for that year. **What triggers loss of eligibility (and the need to cancel)** If the lower earner's income rises so they start using their full Personal Allowance, or the higher earner's income rises into higher-rate tax, the couple typically becomes ineligible and should cancel the claim -- continuing to claim after becoming ineligible can result in HMRC clawing back the allowance later, potentially as an unexpected tax bill. **Practical tip** If you think you may have been eligible for Marriage Allowance in previous years and never claimed, apply promptly rather than delaying -- every tax year that passes the four-year mark becomes permanently irrecoverable, so any hesitation directly costs you money that can no longer be reclaimed.