Marriage Allowance Calculator UK

Check if you and your partner are eligible for Marriage Allowance and see how much you could save — up to £252 per year, or £1,008 if you backdate for 4 years.

Marriage Allowance permits a lower-earning spouse or civil partner to transfer £1,260 of their personal allowance to their partner, reducing the recipient's annual income tax bill by up to £252. To qualify, the transferor must earn below the personal allowance (£12,570) and the recipient must be a basic rate taxpayer.

A frequently overlooked aspect of this relief is the ability to backdate claims for up to four tax years. This means a newly eligible couple can recover up to £1,008 in a single claim. The transfer applies for the entire tax year once registered and continues automatically until cancelled — even if circumstances change mid-year.

HMRC data indicates that 1.8 million couples benefited from Marriage Allowance in 2022/23, yet an estimated 2.4 million eligible couples still fail to claim (HMRC Marriage Allowance Statistics, 2024). This calculator determines your eligibility and calculates the precise saving including any backdated amount.

How to check your Marriage Allowance eligibility

  1. Enter the lower earner's annual income
  2. Enter the higher earner's annual income
  3. Confirm your marital status and the tax year
  4. See your annual saving and any backdated refund available

Written by the CalcStack team · Last updated March 2026

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Frequently asked questions

What is Marriage Allowance?▾
Marriage Allowance lets you transfer £1,260 of your Personal Allowance to your husband, wife, or civil partner. This reduces their tax by up to £252 per year. You must be married or in a civil partnership to qualify.
Who is eligible for Marriage Allowance?▾
You can claim if one partner earns less than £12,570 (the Personal Allowance) and the other earns between £12,571 and £50,270 (basic rate taxpayer). Both partners must have been born on or after 6 April 1935.
How much can I save with Marriage Allowance?▾
The maximum saving is £252 per year. The lower earner transfers £1,260 of their tax-free allowance to the higher earner, who then pays 20% less tax on that amount (£1,260 x 20% = £252).
Can I backdate my Marriage Allowance claim?▾
Yes, you can backdate your claim for up to 4 previous tax years. This means you could receive up to £1,008 in backdated tax relief on top of the current year saving, for a total of up to £1,260.
How do I apply for Marriage Allowance?▾
Apply online at gov.uk/marriage-allowance. The lower earner applies to transfer their allowance. You will need your National Insurance numbers and proof of identity. HMRC will adjust your tax codes automatically.
Does Marriage Allowance affect my tax code?▾
Yes. The person transferring the allowance will have their tax code reduced (e.g., from 1257L to 1145L), and the recipient will have theirs increased (e.g., to 1383L). This is shown as an M or N suffix on the tax code.
What happens to Marriage Allowance if we divorce?▾
Marriage Allowance continues until the end of the tax year in which you separate, unless you or your partner cancels it. If you divorce or dissolve your civil partnership, you should cancel the transfer with HMRC.
Can higher rate taxpayers claim Marriage Allowance?▾
No. The recipient must be a basic rate taxpayer (earning no more than £50,270). If the higher earner pays tax at 40% or 45%, they cannot receive the transferred allowance.
Is Marriage Allowance the same as Married Couples Allowance?▾
No. Married Couples Allowance is a different, older relief for couples where one partner was born before 6 April 1935. It gives a larger reduction. You cannot claim both.
Does Marriage Allowance apply in Scotland?▾
Yes, Marriage Allowance applies in Scotland. However, the saving may differ slightly because Scotland has its own income tax rates. Scottish basic rate taxpayers (19% starter and 20% basic) can still benefit from the transfer.

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