Marriage Allowance Backdate Calculator

If you and your spouse or civil partner were eligible in previous tax years but never claimed, HMRC will let you backdate — worth up to £252 per year. See how many years you can claim for below.

This is an estimate for guidance only, not tax advice. You can only claim for years in which both of you met the eligibility criteria throughout. Confirm and claim directly at gov.uk/marriage-allowance or via HMRC.
Last Verified: 7 August 2026

Estimated total claim

How the figure is worked out

The lower earner can transfer 10% of their Personal Allowance to their spouse or civil partner. For 2022/23 through 2026/27 the Personal Allowance has been frozen at £12,570, so 10% (rounded up to £1,260) transferred and saved at the 20% basic rate works out to £252 per tax year — for every year in this period.

Frequently asked questions

How far back can I backdate a Marriage Allowance claim?

Up to 4 previous tax years, plus the current year — so up to 5 years' worth if you were eligible throughout. From 6 April 2026, the earliest claimable year is 2022/23.

How much is Marriage Allowance worth per year?

Up to £252 per tax year at current rates and allowances.

Who qualifies for Marriage Allowance?

You must be married or in a civil partnership. One partner must earn less than the £12,570 Personal Allowance, and the other must be a basic-rate taxpayer (not paying higher or additional rate tax).

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