The marriage allowance applies to married couples and those in a civil partnership where a spouse or civil partner does not pay tax or pay tax above the basic rate threshold for Income Tax (i.e., one of the couples must currently earn less than the £12,570 personal allowance for 2023-24).

The allowance works by permitting the lower earning partner to transfer up to £1,260 of their personal tax-free allowance to their spouse or civil partner. The marriage allowance can only be used where the recipient of the transfer (the higher earning partner) does not pay more than the basic 20% rate of Income Tax. This would usually mean that their income is between £12,571 and £50,270 in 2023-24. For those living in Scotland this would usually mean income between £12,571 and £43,662.

Making a claim, could result in a saving of up to £252 for the recipient (20% of £1,260), or £21 a month for the current tax year. In fact, even if a spouse or civil partner has died since 5 April 2018, the surviving person can still claim the allowance (if they qualify) by contacting HMRC’s Income Tax helpline.

If you meet the eligibility requirements and have not yet claimed the allowance, you can backdate your claim to 6 April 2019. This could result in a total tax break of up to £1,256 if you can claim for 2019-20, 2020-21, 2021-22, 2022-23 as well as the current 2023-24 tax year. If you claim now, you can backdate your claim for four years (if eligible) as well as for the current tax year. Even if you are no longer eligible or would have been in all or any of the preceding years, then you can claim your entitlement.

HMRC’s online Marriage Allowance calculator can be used by couples to find out if they are eligible for the relief. An application can be made online at GOV.UK.