Audience: Married couples and civil partners
Marriage Allowance is one of the most underused tax benefits available to couples in the United Kingdom. Introduced in 2015, it allows one spouse or civil partner to transfer a portion of their personal allowance to the other, reducing the recipient's income tax bill by up to £252 per year. Yet HMRC estimates that millions of eligible couples have never claimed it.
If you are married or in a civil partnership and one of you earns less than the personal allowance threshold, this guide will help you understand whether you qualify and how straightforward the claiming process is.
To claim Marriage Allowance, several conditions must all be met. You must be married or in a registered civil partnership — simply living together does not qualify. One of you must be a non-taxpayer, meaning your income is below the personal allowance of £12,570 for 2024/25. The other must be a basic rate taxpayer, meaning their income is between £12,571 and £50,270. The benefit is not available to higher or additional rate taxpayers.
The lower-earning partner is the one who makes the transfer. They give up 10% of their personal allowance — £1,260 in 2024/25 — to the higher-earning partner. Since the lower earner was not using that part of their allowance anyway (their income was below the threshold), they lose nothing in practice.
The higher-earning partner receives the transferred allowance, which increases their personal allowance from £12,570 to £13,830. This reduces their taxable income by £1,260, saving them 20% of that amount — £252 in income tax per year.
Applying for Marriage Allowance is straightforward and takes only a few minutes online. The lower-earning partner applies at gov.uk/marriage-allowance using their National Insurance number and date of birth. They will also need their partner's National Insurance number.
Once the application is processed, HMRC will adjust the higher-earning partner's tax code to reflect the additional allowance. Their code will change to include the letter M (indicating they have received a Marriage Allowance transfer), and they will pay slightly less tax each month as a result.
The lower-earning partner's tax code will change to include the letter N, confirming that they have made the transfer. Since their income is below the personal allowance anyway, this has no practical effect on their tax.
One of the most attractive features of Marriage Allowance is that you can backdate a claim for up to four previous tax years, provided you were eligible in those years. This means that a couple who have been eligible since 2020/21 but never claimed could potentially receive a lump sum refund of up to £1,008 (four years at £252 per year).
Backdated claims are paid as a lump sum cheque or bank transfer, rather than through an adjustment to future tax codes. The process is the same as for a current-year claim — simply make the application online and indicate that you wish to backdate.
It is worth checking your eligibility even if your circumstances have changed. If you were eligible for Marriage Allowance in a previous year — even if you are now both working or your earnings have increased — you can still claim the refund for those years.
Once you have applied for Marriage Allowance, it will continue automatically from year to year unless your circumstances change. You do not need to reapply each year. However, you should notify HMRC if the lower-earning partner's income increases above the personal allowance, or if the higher-earning partner's income rises above the basic rate threshold, as the benefit will no longer apply in those circumstances.
Marriage Allowance can also be claimed if one partner has died. If your spouse or civil partner passed away and they were the higher-earning partner who was receiving the transferred allowance, you can still claim the benefit for the tax year in which they died.
It is important not to confuse Marriage Allowance with Married Couple's Allowance, which is a separate and older benefit. Married Couple's Allowance is available only to couples where at least one partner was born before 6 April 1935. It provides a more generous tax reduction of between £4,280 and £11,080 (depending on income) for 2024/25.
If you are eligible for Married Couple's Allowance, you cannot also claim Marriage Allowance — you must choose one or the other. Since Married Couple's Allowance is generally more valuable, older couples should ensure they are claiming the right benefit.
**Disclaimer: ***This article is for general information purposes only and does not constitute tax advice. Tax rules can change and individual circumstances vary. Always consult a qualified tax adviser or contact HMRC directly for advice specific to your situation.*