Marriage Allowance Calculator

The short answer

• The lower earner transfers £1,260 of their Personal Allowance to their spouse or civil partner.
• That cuts the higher earner’s tax by up to £252 a year.
• You can backdate to 2022/23, so a new claim can be worth up to £1,260.
• The lower earner must have income under £12,570, and the higher earner must be a basic-rate taxpayer.

What Marriage Allowance is

Everyone has a Personal Allowance of £12,570, the income they can have before paying Income Tax. If one partner does not use it all, they can transfer 10% of the allowance, £1,260, to the other. The receiving partner then gets a tax reduction of 20% of £1,260, which is £252. The lower earner’s own allowance falls to £11,310, which costs them nothing if their income is below that.

Who can claim

• You are married or in a civil partnership; living together is not enough.
• The lower earner’s income is £12,570 or less (usually they pay no Income Tax).
• The higher earner pays tax at the basic rate: income between £12,571 and £50,270, or up to £43,662 in Scotland.
• Both of you were born on or after 6 April 1935.

You can claim if you live abroad, as long as you get a UK Personal Allowance.

Worked examples

When the lower earner has some income

The transfer reduces the lower earner’s allowance to £11,310. If their income is above that, they start paying tax on the difference. At £12,000 they pay £138 more, and at £12,570 they pay £252 more, cancelling the gain completely. So Marriage Allowance is worth most when the lower earner’s income is under £11,310, such as someone on maternity leave, studying, caring, or retired with a small pension.

When the higher earner pays little tax

The saving is a reduction in tax, so it cannot be more than the tax the higher earner pays. If they earn £13,000, they pay only £86 of Income Tax, so that is all Marriage Allowance can save. The calculator caps the saving at the higher earner’s tax.

Backdating up to four years

You can claim for any earlier tax year since 5 April 2022 in which you were eligible. Each of 2022/23, 2023/24, 2024/25 and 2025/26 is worth up to £252, because the allowance and the transfer have been the same since 2021. HMRC pays backdated amounts as a cheque or bank transfer to the higher earner. The 2022/23 year can only be claimed until 5 April 2027.

Scottish taxpayers

Scottish taxpayers can claim too. The higher earner must not pay more than the intermediate rate of 21%, so their income must be £43,662 or less. The tax reduction is still £252. A lower earner in Scotland whose income is above £11,310 pays the extra tax at the 19% starter rate.

Pensioners and savings income

Many retired couples qualify: for example, one partner on the full new State Pension (£12,547.60 in 2026/27) and the other with a smaller pension. Be careful when the lower earner’s income is close to the limit, as the State Pension alone almost uses the whole allowance. Savings interest covered by the starting rate or Personal Savings Allowance still counts as income for the £12,570 test.

How to claim

1. Online, about 10 minutesThe lower earner applies on GOV.UK

   You need both National Insurance numbers and ID such as a P60 or passport.

2. Within weeksTax codes change

   The higher earner's code gains 126 points; the lower earner's falls.

3. LaterBackdated payments

   HMRC sends a cheque or pays into the higher earner's bank account.

How it shows in your tax code

The higher earner’s tax code ends in M, such as 1383M, and the lower earner’s ends in N, such as 1131N. If either of you completes Self Assessment, the allowance is applied in your tax calculation instead.

When to cancel or update

If your partner dies

If your partner dies, the Marriage Allowance usually continues to the end of that tax year and then stops. Tell HMRC, which will update both tax codes, and check whether a backdated claim can still be made for earlier years when you were both eligible.

Married Couple's Allowance

If either of you was born before 6 April 1935, you cannot get Marriage Allowance but may get Married Couple’s Allowance instead, which is worth more: a tax reduction of over £1,000 a year for most couples who qualify. It is claimed through your tax return or by contacting HMRC.

Avoiding claim firms

Some firms offer to claim Marriage Allowance for you and keep a large share of any refund. Claiming directly on GOV.UK is free and simple. Be wary of texts or emails offering a tax refund: HMRC does not contact people about refunds that way.

Which partner applies

The partner with the lower income makes the application, because they are giving away part of their allowance. The higher earner does not need to do anything, but both of you need your National Insurance numbers to hand. If the lower earner cannot use the online service, for example because they do not have the ID needed to create a Government Gateway account, they can apply by phone to HMRC. If one of you has a power of attorney for the other, the attorney can apply on their behalf. Once accepted, HMRC writes to both of you to confirm, and adjusts both tax codes from the next payday where possible.

If either of you fills in a tax return

If the higher earner completes a Self Assessment return, the tax reduction is applied in their return rather than through PAYE, so any refund appears when the return is processed. If the lower earner files a return, for example because they have a small self-employment income, the return shows their reduced allowance of £11,310. Make sure the incomes on your returns are below the limits for every year you claim: if the lower earner turns out to have had income over £12,570 in a year, HMRC will take the Marriage Allowance back for that year.

Marriage Allowance and benefits

Universal Credit and most other means-tested benefits look at take-home pay after tax, so the higher earner’s lower tax bill slightly increases the household’s earnings for Universal Credit. For most couples the effect is small: Universal Credit falls by 55p for each pound of extra take-home, so £252 of tax saved might reduce Universal Credit by about £139 a year. You are still better off claiming, but the gain is less than £252. Marriage Allowance does not affect Child Benefit, the State Pension or Pension Credit directly.

Common situations where couples qualify

• One partner at home with young children, with little or no income of their own.
• One partner studying full time, with no more than a small part-time income.
• One partner on maternity or shared parental leave for most of the tax year, if their total income for the year stays under £12,570.
• Retired couples where one partner has a small pension and the other a larger one, within the basic-rate band.
• One partner caring for a relative and receiving Carer’s Allowance, which is taxable but well under the allowance.

In each case, check the lower earner’s total taxable income, including any interest above their savings allowances and taxable benefits.

Common mistakes

• Thinking you need a joint income below a limit: only each partner’s own income matters.
• Forgetting backdated years, which can be worth more than the current year.
• Leaving the claim in place after the lower earner’s income rises above £12,570, which leads to tax being owed.
• Assuming couples who live together but are not married can claim: they cannot.

Which tax year your claim covers

A claim made now covers the current tax year, 2026/27, and continues automatically into later years. Backdated years are separate: you choose which earlier years to include when you apply, and each is checked against your incomes for that year. If you apply near the end of a tax year, the higher earner may see the whole year’s saving as a refund rather than through their tax code.

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