Marriage Allowance Calculator

The UK Marriage Allowance is worth £252 a year, and HMRC has long flagged that take-up among eligible couples sits well below where it could be. The form is short. The money is a refund, not a loan. There is no catch. The main reason the take-up rate is so low is that nobody hears about it.

Our Marriage Allowance calculator checks whether you and your spouse or civil partner qualify under the 2026-27 thresholds, shows the £252 annual saving on screen, and tells you how much you can recover by backdating up to four previous tax years.

Contents

• What Marriage Allowance Actually Is
• Who Qualifies in 2026-27
• How to Use the Calculator
• How to Claim and Backdate Four Years
• Why Couples Get Wrongly Told They're Ineligible

What Marriage Allowance Actually Is

Marriage Allowance is a transferable slice of the Personal Allowance, the £12,570 chunk of income every UK adult can earn tax-free. If one partner does not use all of theirs, they can hand 10% of it (£1,260 in 2026-27) to a basic-rate-paying partner. The £1,260 of income that would have been taxed at 20% is now tax-free, and the couple saves £252 per year.

That is the whole mechanic. There is no means test beyond the income thresholds, no asset check, no paperwork beyond the initial claim. Once you apply, HMRC carries the transfer forward automatically every tax year until your circumstances change. The lower earner has to be the one making the claim, because they are giving up the allowance.

The reason it exists is political rather than economic. It was introduced in 2015 to recognise marriage in the tax system, and the £252 number has barely moved with inflation since. It is one of those allowances the Treasury would rather you forgot about, because the Personal Allowance has been frozen at £12,570 since 2021 and is set to stay there until at least 2028. Each year the freeze drags more low earners into tax, the unclaimed Marriage Allowance worth £252 becomes a bigger relative win for couples who do bother to fill in the form.

Who Qualifies in 2026-27

Four conditions all have to be true at the same time:

1. Married or in a civil partnership. Cohabiting couples do not qualify regardless of how long they have lived together or whether they have children.
2. The lower earner's income is under £12,570. Income for this test includes earnings, taxable pensions, taxable savings interest, and most other taxable income before tax. Tax-free income (ISA returns, dividend allowance, personal savings allowance) does not count.
3. The higher earner pays basic-rate tax. Their income must be between £12,571 and £50,270 (the threshold is £43,662 for Scottish residents per gov.uk). Higher and additional-rate taxpayers are excluded by design.
4. Both partners were born after 6 April 1935. Older couples get the more generous Married Couple's Allowance instead, and you cannot claim both.

If those four boxes tick, you qualify. The calculator runs the check for you and surfaces a clear pass or fail in seconds.

How to Use the Calculator

The Marriage Allowance calculator needs two numbers and gives you a verdict in under thirty seconds.

1. Enter the Lower Earner's Annual Income

This is everything taxable the lower-earning partner expects to receive in the 2026-27 tax year before tax: salary, pension drawdown, taxable benefits, and so on. If they earn nothing at all, enter zero. Anything under £12,570 keeps the transfer worth the full £252.

2. Enter the Higher Earner's Annual Income

Gross annual salary or self-employed profit, before tax and pension deductions. If you are not sure of the gross figure, the take-home pay calculator goes the other way: net to gross with all the deductions broken out. Anything between £12,571 and £50,270 puts the higher earner in the basic-rate band and keeps eligibility intact.

3. Read the Verdict

A green "Eligible" panel shows the £252 annual saving plus the maximum backdated lump sum. An amber "Not eligible" panel explains why (usually the lower earner is above £12,570 or the higher earner is above £50,270) so you know what would need to change. The numbers update live as you adjust either income, which is useful for couples weighing up a pay rise or a return-to-work decision against keeping the allowance.

How to Claim and Backdate Four Years

The claim itself is one form on gov.uk/marriage-allowance. The lower earner submits it. You need both National Insurance numbers and a way to verify your identity (driving licence, passport, or recent payslip details). HMRC publishes current processing times on gov.uk.

The part most couples miss is backdating. If you were eligible in any of the four previous tax years (2022-23, 2023-24, 2024-25, 2025-26) but never claimed, HMRC will pay those years out as a lump sum at the same time as switching on the current year. The Personal Allowance has been frozen at £12,570 across all four backdated years, so the saving has stayed at £252 a year, giving a maximum lump sum of around £1,008 across the four prior years plus £252 for the current year. The refund arrives either as a cheque, a bank transfer, or via a tax-code adjustment to the receiving partner's PAYE.

A few hard-earned warnings:

• Think hard before using a tax reclaim agent. Various third-party reclaim firms advertise to file this claim for you in exchange for a cut of the refund. They are filling in the same free form you can submit directly to HMRC, so every pound they keep is a pound HMRC was going to pay you anyway. Check the fees, the deed of assignment, and HMRC's own warnings about repayment agents before signing anything.
• Backdating works year by year. If the lower earner went over £12,570 in 2024-25 but stayed under in the others, only that one year drops out of the claim. You still recover the other three.
• Apply before 5 April to catch the oldest year. The fourth backdate year expires every tax year end, so a claim made on 6 April loses 12 months of potential refund.

Once the claim is in, it auto-renews every year. You only need to revisit it if one of you changes job, retires, or your incomes shift across the thresholds.

Why Couples Get Wrongly Told They're Ineligible

The two most common "you don't qualify" rejections are based on a misunderstanding of how taxable income is calculated, not on a genuine ineligibility.

Higher earner just above £50,270. A partner earning £52,000 looks like they are out of the basic-rate band and therefore out of Marriage Allowance. But if they pay £2,000 a year into a SIPP or a workplace pension via salary sacrifice, their adjusted net income for tax purposes drops to £50,000. They are back inside the basic-rate band and back inside eligibility. The same logic applies to Gift Aid donations. The calculator does not see your pension contributions, so if you are within a few thousand pounds of £50,270, do the SIPP/pension adjustment in your head before reading the verdict.

Lower earner has a small private pension. People assume pension income is somehow exempt, but taxable pension drawdown counts toward the £12,570 ceiling the same way salary does. A retired partner taking £14,000 from a SIPP is no longer eligible to make the transfer, even though they "don't work". On the other hand, the 25% tax-free lump sum from a pension does not count, neither do ISA withdrawals, so the eligibility maths is friendlier than it first looks for retirees who are drawing money strategically.

One partner is on maternity leave. Statutory Maternity Pay is taxable income. If you take a full year off and your SMP plus any return-to-work pay stays under £12,570, you become the eligible lower earner for that tax year and can transfer to your partner. This is one of the cleanest wins available to new parents, and the maternity pay calculator gives you the SMP figure to plug in.

Anything close to the threshold deserves a recalculation before you write off the claim.