Marriage Allowance Calculator
Enter both incomes to see whether Marriage Allowance applies, how much tax you’d save this year, and what a backdated claim could be worth. The result is the net household saving — it already accounts for any tax the transferring partner starts to pay.
How it works
Marriage Allowance lets the lower earner in a marriage or civil partnership transfer £1,260 of their personal allowance (10% of £12,570) to their partner. The recipient’s tax bill falls by 20% of the transferred amount — up to £252 a year.
A clean worked example: one partner earns £8,000, the other £30,000. The lower earner transfers £1,260 of allowance; their own income stays below the reduced £11,310 allowance, so they pay no extra tax, and the recipient’s bill falls by £1,260 × 20% = £252. Enter those two figures above and £252 is exactly what the calculator returns.
It only pays off when the lower earner isn’t using all of their allowance and the higher earner pays basic-rate tax — income between £12,571 and £50,270 (different bands apply to Scottish taxpayers). If the higher earner pays 40% tax, you cannot claim.
If the lower earner’s income is above £11,310 (the reduced allowance after transfer), part of the saving is clawed back as their own tax rises — the calculator nets this off. With the lower earner on £12,000, for example, £690 of their income becomes taxable at 20% (£138), so the household keeps £252 − £138 = £114 rather than the full £252. Claims can be backdated up to 4 tax years, so a first claim can be worth over £1,000.
Who is not covered: couples who live together but are not married or in a civil partnership cannot claim at all, however long they have been together. Couples where either partner was born before 6 April 1935 should look at Married Couple’s Allowance instead — it is usually worth more, and you cannot have both.
Two mistakes to avoid. The transfer is all-or-nothing: you cannot transfer less than the full £1,260, which is why the clawback arithmetic above matters. And the claim keeps running automatically each year once made — if the higher earner later moves into the 40% band, or the marriage ends, you need to cancel it rather than assume HMRC will notice.
FAQ
Who qualifies for Marriage Allowance?
You must be married or in a civil partnership (living together as a couple is not enough), the lower earner must normally have income below the £12,570 personal allowance, and the higher earner must be a basic-rate taxpayer with income between £12,571 and £50,270. Couples where either partner was born before 6 April 1935 should look at Married Couple’s Allowance instead, which is usually worth more.
How much is Marriage Allowance worth?
Up to £252 per tax year: £1,260 of allowance transferred × the 20% basic rate. Because claims can be backdated up to 4 tax years, a couple claiming for the first time can receive a lump-sum refund of £1,000 or more for past years plus the ongoing annual saving. The claim continues automatically each year until you cancel it or your circumstances change.
How do I apply for Marriage Allowance?
Apply free on gov.uk — the LOWER earner makes the application, using their Government Gateway account, National Insurance numbers for both partners and ID. HMRC then adjusts the recipient’s tax code (usually to an “M” suffix code) or their Self Assessment. Avoid third-party websites that charge a fee or take a cut of the refund; the official claim costs nothing.
What if the lower earner has some income above £11,310?
The transfer is all-or-nothing (£1,260), so after transferring, the lower earner’s own allowance drops to £11,310 and income above that becomes taxable at 20%. The couple still gains overall as long as the lower earner’s income is below £12,570 — the recipient’s £252 saving simply shrinks by the extra tax the transferor pays. This calculator shows the net household saving.
Can we claim if we live together but aren’t married?
No. Marriage Allowance is strictly limited to married couples and civil partners — cohabiting couples cannot claim regardless of how long they have lived together or whether they have children. It is one of the few remaining tax breaks where the legal status of the relationship, not the living arrangement, is what counts.
What happens if the higher earner moves into the 40% band?
The couple stops qualifying: Marriage Allowance requires the recipient to be a basic-rate taxpayer with income between £12,571 and £50,270. Because a claim continues automatically each year until cancelled, a pay rise that pushes the recipient over £50,270 means you should cancel the claim — otherwise HMRC will unwind the ineligible years later.
Do we have to reapply every year?
No — one application keeps the transfer running automatically in each subsequent tax year until you cancel it or your circumstances change. That convenience cuts both ways: it means no annual paperwork while you qualify, but also that it is on you to cancel when you stop qualifying, for example after a divorce or once the higher earner crosses into the 40% band.
Is it still worth claiming if the lower earner is on £12,000?
Usually yes, but the saving shrinks. After transferring, the lower earner’s allowance is £11,310, so £690 of their £12,000 income is taxed at 20% — £138. The recipient still saves £252, leaving a net household gain of £114. The calculator does this netting-off automatically, which is why it asks for both incomes rather than just the higher one.