Marriage Allowance is worth £252 a year and can be backdated four years. Who qualifies in 2026/27, how to claim, and the tax codes it puts on your payslip.
Marriage Allowance is the closest thing UK tax has to free money, and roughly a million eligible couples still do not claim it. It takes about ten minutes online, it is worth £252 a year, and once it is set up it keeps running until you tell HMRC to stop.
The catch is that it is easy to misunderstand who qualifies. It is not a married couples discount. It is a transfer of unused personal allowance from one person to the other, which means one of you has to be genuinely under the tax threshold for it to work at all.
If you are married or in a civil partnership, and one of you earns less than the £12,570 personal allowance, that person can hand £1,260 of their unused allowance to the other, provided the other is a basic rate taxpayer.
That is the whole mechanism. The £1,260 is 10 per cent of the personal allowance, rounded to the nearest £10. The receiving partner would have paid 20 per cent tax on that £1,260, so the couple saves £252 a year. The rules are on gov.uk.
HMRC does not send you a cheque each month. It changes both of your tax codes, and the money arrives as slightly lower deductions on the receiving partner’s payslip.
N. Their allowance drops from £12,570 to £11,310, so the standard code becomes 1131N.M. Their allowance rises from £12,570 to £13,830, so the standard code becomes 1383M.Worked example, using the pairing that comes up most often in the NetPay inbox. He is a nurse on £35,000. She works part time in a school office on £8,000.
Without the transfer, on code 1257L:
With the transfer, on code 1383M:
Her side of it costs nothing. Her allowance falls to £11,310, but she only earns £8,000, so she still pays no income tax at all. The £4,570 of allowance she was never going to use has been partly put to work.
National Insurance is untouched by any of this. The transfer moves income tax allowance only, so his NI stays at 8 per cent on monthly earnings between £1,048 and £4,189 exactly as before. If you were expecting a bigger difference on the payslip, that is why.
If the receiving partner files a Self Assessment return rather than sitting purely on PAYE, the benefit shows up as a reduction in the final tax bill instead of a code change. Same £252, different route.
The clean case is one partner well under £12,570 and one comfortably inside the basic rate band. Claim it, forget it, collect £252 a year.
Three situations need a second look.
If the lower earner is on, say, £12,000, transferring £1,260 drops their allowance to £11,310 and they start paying tax on £690 of their income, which is £138 at 20 per cent. The higher earner still saves the full £252. Net gain for the household: £114. Smaller, but still a gain.
Where it tips over is if the lower earner is already above £12,570. At that point they are not the lower earner in the sense the rules mean, and HMRC will usually reject or unwind the claim.
The receiving partner must be a basic rate taxpayer. For 2026/27 that means taxable income up to £50,270. If a bonus, overtime run, or pay rise pushes them into the higher rate band, they are no longer eligible and the claim should be cancelled for that year. The rate bands are published on gov.uk.
Scotland is the exception worth knowing about. Scottish taxpayers use different rate bands, and eligibility there is based on the receiving partner paying the starter, basic or intermediate rate rather than the UK basic rate. The £252 value is the same.
Marriage Allowance requires a marriage or a civil partnership. There is no common law version of it in UK tax. This is the single most common reason a claim gets refused.
The lower earner makes the claim. This trips people up constantly, because the person who benefits on their payslip is the other one.
You can also apply by post on form MATCF, or by ringing HMRC on 0300 200 3300 if you would rather talk to someone.
Backdating is where the real money is. You can claim for the current tax year plus the four previous ones, provided you were eligible in each. Because the personal allowance has sat at £12,570 since 2021/22, every one of those years is worth the same £252. Claim 2026/27 alongside four backdated years and you are looking at a little over £1,200.
The current year comes through as a tax code change. The closed years are repaid separately, normally by bank transfer or cheque, and that part can take a couple of months.
Here is what I would check a month after applying. Pull up the receiving partner’s payslip and look at the code. If it still says 1257L, the claim has been made but the employer has not picked up the new code yet. That is a payroll problem, not an HMRC one, so ring your payroll team rather than the tax office. And if you see 1383M W1 or 1383M M1, the code is being run non cumulatively, which means the relief is only being applied from that month forward rather than backdated across the year. It sorts itself out at the next full reconciliation, but it is worth knowing why the first month looked smaller than £21.
Tell HMRC if you divorce or dissolve the civil partnership, if the lower earner’s income rises above £12,570, or if the receiving partner moves into the higher rate band. If you do not, HMRC will eventually reconcile it and claw the difference back, usually through next year’s tax code.
One quirk to plan for: if you cancel, the change normally applies from the start of the next tax year rather than immediately, unless the reason is a divorce or bereavement.
The numbers did not move. The personal allowance is still £12,570, the transfer is still £1,260, and the saving is still £252, because the allowance freeze runs through to April 2028.
What did change in April 2026 is how you find out. HMRC now issues most P2 tax code notices digitally rather than by post, so the code change confirming your claim lands in your HMRC online account. If you applied earlier this year and never saw a letter, that is not a failed claim, it is the notice sitting in the app.
The other 2026 wrinkle is the growing number of couples caught by the higher rate edge. With the £50,270 threshold frozen too, pay rises are quietly pushing basic rate taxpayers over the line, a process usually called fiscal drag. If the receiving partner crossed £50,270 for the first time this year, the claim needs cancelling.
1131N on one payslip and 1383M on the other. That is the claim working.If you want to see what a code change like 1383M actually does to your monthly take-home, the NetPay app works it out from your real pay, including National Insurance, pension and student loan. Free to download.
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£252 for the 2026/27 tax year. The lower earner transfers £1,260 of their personal allowance to their partner, and because the receiving partner is a basic rate taxpayer, that £1,260 saves them 20 per cent, which is £252. It is the same figure it has been every year since 2021/22, because the personal allowance has been frozen at £12,570 throughout.
You must be married or in a civil partnership. One of you needs an income below the £12,570 personal allowance, and the other needs to be a basic rate taxpayer, which for 2026/27 means income between £12,571 and £50,270. Living together without being married or civil partnered does not qualify, however long you have been together.
Yes, by up to four previous tax years, as long as you were eligible in each of those years. The personal allowance has been £12,570 since 2021/22, so each backdated year is worth £252. Claim the current year plus four backdated years at once and you can get a little over £1,200 back, usually paid by cheque or bank transfer for the closed years.
The partner giving the allowance away gets a code ending in N, typically 1131N. The partner receiving it gets a code ending in M, typically 1383M. If you see an N or an M on your payslip and you never applied for Marriage Allowance, ring HMRC on 0300 200 3300, because the link may have been set up incorrectly.
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A note on financial advice: NetPay UK calculates take-home pay based on official HMRC tax rules. This article reflects rules in force at the time of publication (29 August 2026). Tax rules change. For complex situations, consult a qualified UK accountant or visit gov.uk/income-tax.
