The £1,260 Question Hiding in Your Marriage Certificate
Photo: Sandra White, CC BY-SA 2.0, via Wikimedia Commons
Most people file Marriage Allowance under 'things to do after the wedding' and then forget it. But this isn't a confetti-and-cake perk. It's a straightforward tax allowance, and for some couples it has been quietly sitting unclaimed for years.
What Marriage Allowance actually does
Under current rules for 2026/27, the standard Personal Allowance is £12,570. Marriage Allowance lets one partner transfer 10% of their Personal Allowance — £1,260 — to the other. The receiving partner then pays less tax. For a basic-rate taxpayer, that £1,260 is worth £252 over the year.
It is not a cash payout. It's a reduction in tax, usually delivered through your tax code if you're employed, or through self assessment if you file a return. You don't need an accountant and you don't need to be newly married. Civil partners qualify too.
Who can actually use it?
The shorthand is: one partner needs to be a non-taxpayer, and the other needs to be a basic-rate taxpayer.
In practice, that means the partner transferring the allowance should have income below their Personal Allowance. The partner receiving it should not be paying higher or additional rate tax. That's where assumptions get people into trouble.
A lot of couples look at one salary, decide it's 'too high', and never check. But the income HMRC uses isn't always the same as the headline salary on your contract. Pension contributions, salary sacrifice arrangements and other adjustments can change the picture. If you're near the basic-rate limit, it's worth running the numbers rather than self-rejecting.
The same goes for the lower earner. A part-time job, a small pension, or a year with a gap in work can put someone under the threshold without them realising. If you've retired and your only income is a modest pension, check. If you dropped to two days a week after childcare, check.
The four-year queue most people miss
Here's the bit that makes this more than a £252 exercise. Marriage Allowance can be backdated by four tax years.
In the 2026/27 tax year, that means you may be able to claim for 2022/23, 2023/24, 2024/25 and 2025/26 as well as the current year. Each tax year is looked at separately, so you don't need to have been eligible for all of them. But if you have been eligible throughout, the cumulative relief could be around £1,260.
That's not a fortune, but it's also not nothing. It's a boiler service, a few weeks of grocery top-ups, or the difference between a tight January and a manageable one. And unlike a lot of money advice, this one mainly requires admin, not sacrifice.
A worked example
Priya works part-time in a local authority office and earns £9,800. Her husband Tom earns £34,000. Priya's income is below the £12,570 Personal Allowance, so she can transfer £1,260 to Tom. Tom is a basic-rate taxpayer, so the transfer reduces his tax by £252 for the year.
If they'd been in the same position since 2022/23 and had never claimed, they could be looking at up to £1,260 across five tax years — the four backdated years plus 2026/27. If Priya's hours were higher in one of those years and her income went above the threshold, that year would drop out. That's why the claim is year by year, not all-or-nothing.
Now imagine Priya had assumed she earned 'too much' because she once did overtime in 2023. She might never have checked. A ten-minute look at the actual figures could have changed that.
How to claim without paying someone
Go to GOV.UK and search for Marriage Allowance. You can apply online, and it's free. You'll need National Insurance numbers for both of you and some basic details. If you're employed, HMRC will usually adjust the receiving partner's tax code. If you file a self assessment return, the allowance should be reflected there.
If you're not sure whether you qualify, use the government's online checker before assuming. Don't pay a claims company to do this. There are firms that charge a percentage of backdated claims for something you can do yourself in the time it takes to drink a cup of tea.
One more thing: don't backdate a claim for a year when the lower earner actually paid tax. That's not the point of the allowance, and HMRC will correct it. The claim is for transferring unused allowance, not for inventing one.
The takeaway
Marriage Allowance is easy to overlook because it doesn't arrive as a letter with a deadline. It sits in the tax system, waiting for someone to ask. If you're married or in a civil partnership, and one of you earns below the Personal Allowance while the other pays basic rate, it's worth ten minutes this week.
Check the current year. Then check the four years behind it. The worst outcome is that you find out you're not eligible. The best outcome is a tax code change and a backdated payment you'd otherwise never have seen.
