How does Marriage Allowance work?

The full mechanic, step by step

Marriage Allowance is a transfer of a slice of one spouse's Personal Allowance to the other. In the 2026/27 tax year the transfer amount is fixed at £1,260 — exactly 10% of the standard Personal Allowance of £12,570. Once HMRC processes the election, the lower earner's allowance falls to £11,310 and the higher earner's effective allowance rises to £13,830. The recipient saves tax at their marginal rate on the £1,260 — usually 20%, giving the headline saving of £252 per year.

The saving never works out as the full £1,260 because the transferred allowance only reduces the recipient's tax — it does not give them a cash refund. If the recipient is in the basic-rate band, the saving is exactly 20% of £1,260. If the lower earner had any taxable income above £11,310 after the transfer, they pay tax on that overflow at 20% — which is why the scheme works best when the lower earner is well below the standard Personal Allowance.

Who actually benefits

The classic case: one spouse earns £6,000 from a part-time job, the other earns £30,000. The lower earner has £6,570 of unused Personal Allowance, more than enough to make the £1,260 transfer worthwhile. The recipient saves £252 and the lower earner pays no tax either way. Net household saving: £252.

The case where it does not work: both spouses earn above the Personal Allowance, or the recipient earns above £50,270 and is therefore a higher-rate taxpayer. Higher-rate taxpayers do not qualify for the recipient role in Marriage Allowance — that is a deliberate cliff in the rules. Scotland has its own intermediate rate band, but the same broad principle applies: if the recipient is paying tax above the basic rate, the election is unavailable.

How to claim and backdate

Either spouse can apply via gov.uk; the lower earner is the one making the election to transfer. Once granted, the election rolls over automatically each tax year until cancelled. Marriage Allowance can be backdated up to four tax years if both partners would have qualified in those earlier years — claims for 2022/23 and onward are still open and can be worth roughly £1,000 in total backdated savings if all four years are eligible.

If circumstances change — for example, the lower earner takes a higher-paid job and now uses all of their Personal Allowance, or the higher earner crosses into higher-rate territory — the couple should cancel the election or HMRC may issue a balancing assessment. The cancellation typically takes effect from the start of the next tax year.

Common mistakes

• Higher earner is on a tax code that already applies the credit. If the recipient's tax code includes the suffix "M", the saving is built into PAYE; do not also claim a refund through Self Assessment.
• Forgetting to cancel after divorce or bereavement. The election survives administratively until cancelled. HMRC reconciles in arrears.
• Confusing it with the Married Couple's Allowance, which is a different (much more generous) relief that only applies if at least one partner was born before 6 April 1935.

Related on this site

Use the Marriage Allowance checker for a first-pass couple estimate, the tax calculator to model the recipient's overall position, and the adjusted net income calculator if either partner is near the higher-rate threshold and trying to plan around it.

The headline numbers

In 2026/27, the transfer amount is £1,260 and the usual maximum tax saving is £252. The saving is not the whole transferred amount because the tax reduction is usually worth 20% of the transfer.

The usual conditions

• You must be married or in a civil partnership.
• The lower earner needs unused Personal Allowance to transfer.
• The recipient partner normally needs to stay within the basic-rate range for the scheme to work cleanly.

Best next page

Use Marriage Allowance Checker for a first-pass couple estimate, and see the official GOV.UK page for the formal rules and application route.

Official source: How Marriage Allowance works.

Worked example: the arithmetic in full

Consider Tom and Aisha in 2026/27. Aisha works part-time and earns £9,000; Tom earns £35,000. Step by step:

• Aisha’s income (£9,000) is below the £12,570 Personal Allowance, so she pays no tax and has £3,570 of allowance going unused. She can spare the £1,260 transfer.
• Aisha elects to transfer £1,260. Her allowance drops to £11,310 — still above her £9,000 income, so she still pays no tax.
• Tom’s effective Personal Allowance rises to £13,830. Because he is a basic-rate taxpayer, the extra £1,260 of tax-free income saves him 20% × £1,260 = £252.
• Household result: £252 better off for the year, for a few minutes of admin.

Change one number and it can fail. If Aisha earned £12,000, transferring £1,260 would cut her allowance to £11,310 and create £690 of taxable income for her (taxed at 20% = £138). Tom still saves £252, so the couple is £114 ahead — worth doing, but no longer the full £252. And if Tom earned £55,000 he would be a higher-rate taxpayer and ineligible to receive the allowance at all, so the election simply could not be made.

Subtle cases: savings income and bereavement

A non-obvious eligibility point: it is your tax band, not just your salary, that matters for the recipient. Someone can be pushed into the higher-rate band by savings or dividend income on top of earnings, and that disqualifies them from receiving the allowance. Conversely, the lower earner’s spare allowance is most valuable when their income — including any savings interest and dividends — genuinely sits below £11,310 after the transfer, so check both partners’ total taxable income, not just wages, before applying. Where the lower earner relies on the starting rate for savings, transferring allowance can occasionally interact with that relief, so model the whole position if savings interest is significant.

Bereavement is handled more generously than people expect. If a spouse or civil partner dies, the surviving partner can still backdate a Marriage Allowance claim across the open years (up to four), and a claim can even be made after the death for years in which the couple qualified. That can produce a useful lump-sum repayment for a widow or widower who never got around to claiming while their partner was alive. As with all backdating, each year is tested on its own facts — both partners must have met the conditions in the year being claimed.