Part of our complete guide to personal tax reliefs.
What Marriage Allowance actually does
Marriage Allowance lets one partner in a marriage or civil partnership transfer 10% of their personal allowance to the other, provided the person transferring it earns below the personal allowance themselves, and the person receiving it is a basic-rate taxpayer. It's a genuinely simple idea: if one partner isn't using their full tax-free allowance, let the other partner benefit from the unused portion instead of it going to waste.
Who it's actually for
- One partner earning below the personal allowance, often because they're not working, working part-time, or have low self-employment income
- The other partner a basic-rate taxpayer, Marriage Allowance isn't available if the receiving partner is a higher or additional rate taxpayer
- Married couples and civil partners only, it doesn't extend to couples who live together without being married or in a civil partnership
Key point: This isn't automatic, even if you're eligible, you have to actively claim it through HMRC. Plenty of eligible couples simply haven't got round to applying, which means they're leaving a genuine, recurring saving unclaimed every single tax year.
Backdating: the part most people miss
You can claim Marriage Allowance for the current tax year and backdate the claim up to four previous tax years, provided you were eligible throughout each year you're claiming for. For a couple who's been eligible for several years but never claimed, backdating can produce a meaningful lump sum refund in addition to the ongoing annual saving, it's worth checking even if you assume you've missed the boat.
How to apply
The lower-earning partner applies through HMRC, either online via the government gateway or by phone, it's the non-taxpaying or lower-earning partner who makes the application, not the one who benefits. Once approved, the higher earner's tax code updates to reflect the increased allowance, and any backdated years are usually paid as a refund directly.
Not sure if you're eligible, or want help backdating a claim? Book a free consultation and we'll check your eligibility across the last four tax years as part of our Self Assessment service.
Frequently asked questions
Who is eligible for Marriage Allowance?
You must be married or in a civil partnership, one partner must earn below the personal allowance, and the other must be a basic-rate taxpayer, not a higher or additional rate taxpayer, for the transfer to apply.
How much is Marriage Allowance worth?
The lower earner can transfer 10% of their personal allowance to their partner, reducing the partner's tax bill by up to the value of that transferred amount multiplied by the basic tax rate.
Can Marriage Allowance be backdated?
Yes, you can claim for the current tax year plus the previous four tax years if you were eligible throughout, which can add up to a meaningful lump sum if you've never claimed before.
Does claiming Marriage Allowance affect our individual tax records?
Yes, the lower earner's personal allowance is reduced by the amount transferred, and the higher earner's tax code changes to reflect the increased allowance, so both tax codes are affected.