Marriage Allowance lets you transfer £1,260 of your personal allowance to your husband, wife or civil partner. In 2026/27 that cuts their tax bill by up to £252 a year. To qualify, one of you must earn below the £12,570 personal allowance and the other must be a basic-rate taxpayer.
It's one of the simplest tax breaks HMRC offers, yet millions of eligible couples never claim it. This guide explains exactly how it works, who's eligible, and how to apply for free.
What is Marriage Allowance?
Marriage Allowance is a tax perk for married couples and civil partners. It allows the lower earner to hand over part of their unused personal allowance to their partner. Specifically, you transfer £1,260 of the £12,570 tax-free personal allowance.
The receiving partner then pays tax on £1,260 less of their income. At the 20% basic rate, that's a saving of £252 for the year. The benefit is usually applied by adjusting the higher earner's tax code.
According to HMRC, around 2.1 million couples claim Marriage Allowance each year, but many more are thought to be missing out. If that's you, it's worth a few minutes to check.
Who qualifies for Marriage Allowance?
You need to meet three conditions to claim. Get all three right and the saving is straightforward.
- You're married or in a civil partnership. Living together doesn't count, however long you've been a couple.
- The lower earner has income below £12,570. This is the person giving up part of their personal allowance.
- The higher earner is a basic-rate taxpayer. Their income must fall between £12,571 and £50,270 in 2026/27.
If the higher earner is a 40% or 45% taxpayer, you can't claim. In Scotland the higher earner generally needs to be a starter, basic or intermediate-rate taxpayer, roughly up to £43,662.
How much can you save?
For the 2026/27 tax year, the maximum saving is £252. That's £1,260 transferred, taxed at the 20% basic rate.
The exact benefit depends on the lower earner's income. If they earn a little under £12,570, some of the transferred allowance may effectively be needed against their own income. Our Marriage Allowance calculator works out the real-world figure for your situation.
How to backdate up to four tax years
Here's where it gets interesting. You can backdate a claim by up to four tax years, so a claim made in 2026/27 can reach back to 6 April 2022 where you were eligible.
That means claiming for 2022/23, 2023/24, 2024/25 and 2025/26 alongside the current year. The maximum saving for each year sits between £250 and £252, so a full backdated claim can be worth well over £1,000 as a lump sum.
HMRC usually pays backdated amounts by cheque or bank transfer. You only claim once, then the allowance carries forward automatically each year until you cancel it.
How to apply free on GOV.UK
Apply directly through GOV.UK and it costs nothing. The lower earner makes the claim, and you'll need both partners' National Insurance numbers plus a form of ID.
Beware copycat websites. Some paid sites charge a fee, or take a cut of your refund, to submit a claim you could make yourself for free. Search "Marriage Allowance" on gov.uk and use the official page only.
You can also claim by phone or through Self Assessment if you already file a return. Whichever route you choose, never pay a third party for this.
When Marriage Allowance isn't worth it
It doesn't help every couple. If the lower earner uses their full £12,570 personal allowance, transferring part of it could push some of their own income into tax.
It's also unavailable if the higher earner pays 40% or 45% tax. And if both of you earn under £12,570, neither pays income tax anyway, so there's nothing to save.
Run your numbers first. A quick check avoids accidentally creating a small tax bill for the lower earner.
Marriage Allowance vs Married Couple's Allowance
These two are often confused, but they're different. Married Couple's Allowance is the older, more generous relief, and it's only for couples where one partner was born before 6 April 1935.
Married Couple's Allowance reduced tax bills by between £427 and £1,108 in the 2025/26 tax year, and the range is uprated every April — check GOV.UK for the current figures. If either of you was born before that date, check Married Couple's Allowance first, as you can't claim both.
Everyone else uses Marriage Allowance, the £252 relief described above.
What happens if your circumstances change?
Life moves on, and so does your eligibility. You should tell HMRC if things change so your tax codes stay correct.
- Divorce or dissolution. You can cancel the allowance, and it stops from the start of the next tax year unless you cancel jointly.
- Income crosses a threshold. If the higher earner becomes a 40% taxpayer, or the lower earner's income rises above £12,570, the claim may no longer suit you.
- Bereavement. A surviving partner can still benefit, and backdated claims may apply.
Cancelling is done through GOV.UK too, and again it's free.
Check your saving in seconds
Marriage Allowance is easy money for the right couple, and backdating can turn it into a useful lump sum. The hard part is just checking whether you qualify.
Use our free Marriage Allowance calculator to see your 2026/27 saving and your potential backdated refund before you apply on GOV.UK.
This article is general information for the 2026/27 tax year and not personal tax advice. Check your own circumstances with HMRC or a qualified adviser.