Tax
TL;DR
The marriage allowance lets one spouse or civil partner transfer £1,260 of their personal allowance to the other, reducing the higher-earning partner's tax bill by up to £252 per year. To qualify, the lower earner must have income below the personal allowance (£12,570) and the higher earner must be a basic-rate taxpayer. Claims can be backdated up to four tax years, potentially generating a lump sum repayment. Claims are made via HMRC's online service.
Key facts (2026)
- The marriage allowance allows the transfer of up to £1,260 of the personal allowance from one spouse or civil partner to the other, saving the recipient up to £252 in income tax per year (HMRC 2025/26).
- The lower-earning spouse must have income below the personal allowance of £12,570; the higher-earning spouse must be a basic-rate taxpayer (income between £12,571 and £50,270 in 2025/26) - higher-rate taxpayers are not eligible to receive the transfer (HMRC marriage allowance rules).
- Claims can be backdated to the 2021/22 tax year (the four-year limit under standard HMRC claim rules); a backdated claim covering four years generates a maximum repayment of approximately £1,008 for eligible couples who have not previously claimed (HMRC time limits for claims).
- The marriage allowance is applied by reducing the recipient's tax code by 1,260, which reduces the tax deducted through PAYE; the lower earner's tax code is increased by the equivalent amount (HMRC PAYE code adjustment process).
- The allowance ceases to apply in the year of divorce or dissolution of civil partnership; where a partner dies, the surviving partner can still claim the marriage allowance for that tax year (HMRC marriage allowance ending guidance).
How the marriage allowance works in practice
The marriage allowance operates by allowing the lower-earning spouse or civil partner to transfer £1,260 of their personal allowance to their higher-earning partner. The higher earner's personal allowance effectively increases from £12,570 to £13,830, reducing the amount of their income taxed at basic rate. At 20 percent, this saves £252 in income tax (£1,260 x 20 percent). The lower earner does not lose this allowance in a way that costs them money: if their income is below £12,570 they are not paying tax anyway, so the transferred allowance has no tax value to them personally. HMRC adjusts the tax codes of both partners to reflect the transfer; the recipient's code includes an M suffix (indicating marriage allowance received) and the transferor's code includes an N suffix (indicating marriage allowance transferred).
Who qualifies: the income conditions in detail
To qualify for the marriage allowance, the couple must be legally married or in a registered civil partnership (cohabiting couples do not qualify). The lower-earning partner must have income in the tax year that does not exceed £12,570 (the personal allowance for 2025/26). Income for this purpose includes employment income, self-employment profits, pension income, rental income and savings interest - the full picture of taxable income from all sources. The higher-earning partner must pay income tax at the basic rate (20 percent), meaning their income must be between £12,571 and £50,270 in 2025/26. If the higher earner's income is in the higher-rate band (above £50,270), they are not eligible to receive the transferred allowance. In Scotland, the income bands differ; the eligibility for the higher earner is based on Scottish income tax bands rather than the UK-wide bands.
How to make a claim: the HMRC online process
The marriage allowance is claimed through HMRC's online service at gov.uk/apply-marriage-allowance. The lower-earning partner makes the claim by logging in with their Government Gateway credentials. They will need their National Insurance number and their partner's NI number and date of birth. The claim is straightforward and takes approximately ten minutes. HMRC then adjusts the tax codes of both partners; the higher earner will receive an updated tax code notification. The saving is delivered through the PAYE system as reduced monthly tax deductions rather than as a cash payment directly. For the backdated element covering previous tax years, HMRC issues a repayment to the higher earner by cheque or bank transfer after processing the claim.
Backdating the claim: the four-year calculation
HMRC allows marriage allowance claims to be backdated to the 2021/22 tax year (four tax years back from 2025/26). The saving for each backdated year is calculated at the rate applicable in that year; the standard saving has been £252 per year since 2020/21 when the allowance was fixed at £1,260. Backdating claims for all four eligible years therefore generates a maximum lump sum repayment of approximately £1,008, paid by HMRC to the higher earner. The couple must have met the eligibility conditions in each of the backdated years for those years to qualify. If eligibility was not met in one or more of the backdated years - for example, because the lower earner had income above the personal allowance in one year - that year is excluded from the backdated claim.
The marriage allowance and self-assessment
If either partner already completes a self-assessment tax return, the marriage allowance claim should be made through self-assessment rather than the standalone online service. The relevant box in the SA100 return covers the marriage allowance transfer. Self-assessment taxpayers who have been eligible for the marriage allowance but have not claimed it in previous returns can amend those returns within four years to include the claim. PAYE-only couples who do not file self-assessment returns use the separate online claim service, with HMRC adjusting tax codes based on the information provided. If the higher earner becomes a self-assessment taxpayer after making the marriage allowance claim, they must also declare the transferred allowance in their return.
When the marriage allowance ends or changes
The marriage allowance automatically continues from year to year once claimed, unless one partner cancels it or circumstances change. It should be cancelled if: the lower earner's income increases above the personal allowance (they should cancel the transfer, otherwise they will owe tax they would not otherwise have paid); the higher earner's income rises above £50,270 (making them ineligible); the couple divorces or dissolves the civil partnership; or one partner dies. If a partner dies during the tax year, the surviving partner can claim the allowance for that full year. HMRC's systems do not automatically cancel the marriage allowance on divorce; the lower-earning ex-partner must actively cancel it through their personal tax account to avoid the transfer continuing incorrectly.
Related guides
Frequently asked questions
Can I claim the marriage allowance if my spouse is self-employed?
Yes. The marriage allowance is available regardless of whether either partner is employed, self-employed or retired. What matters is the level of income in the tax year, not its source. A self-employed spouse with profits below £12,570 can transfer the allowance to an employed partner who is a basic-rate taxpayer. The self-employed partner would make the claim through the self-assessment return or through the HMRC online service.
What happens if I claim the marriage allowance and my income goes above the personal allowance mid-year?
If the lower earner's income exceeds the personal allowance during the tax year, the transfer may result in the lower earner having too little personal allowance and owing tax. You should cancel the marriage allowance transfer as soon as you expect your income to exceed £12,570. Cancellation is done through your personal tax account. HMRC will adjust the tax codes for the remainder of the year and reconcile any underpayment at the end of the year through self-assessment or a Simple Assessment.
Does the marriage allowance apply in Scotland?
Yes, but with a modification. The eligibility for the higher-earning partner is assessed against Scottish income tax bands rather than UK-wide bands. In Scotland, the higher earner must be a Scottish starter, basic or intermediate rate taxpayer (not higher or top rate). The Scottish bands differ from England, Wales and Northern Ireland, so the effective income range for eligibility is different. The HMRC marriage allowance guidance on gov.uk includes specific notes for Scottish taxpayers.
Can cohabiting couples claim the marriage allowance?
No. The marriage allowance is restricted to legally married couples and registered civil partners. Cohabiting couples, regardless of how long they have been together or whether they have children, are not eligible. This is one of the financial benefits that marriage and civil partnership provide over cohabitation under current UK tax law.
What happens to the marriage allowance after separation?
If you separate but are not yet legally divorced or have not dissolved the civil partnership, you remain technically eligible for the marriage allowance. However, if the financial circumstances that qualified you have changed (for example, the lower earner now has income above the personal allowance, or the higher earner is now higher-rate), the transfer should be cancelled. Upon legal divorce or dissolution, the marriage allowance ends for the year of the legal separation; neither ex-partner can claim it in subsequent years.
How we verified this guide
Marriage allowance transfer amount and saving were confirmed from HMRC's 2025/26 marriage allowance guidance. Backdating time limit was confirmed from HMRC's standard four-year claim window rules. Scottish taxpayer eligibility note was confirmed from HMRC's Scotland-specific marriage allowance guidance. Death provisions were confirmed from HMRC's marriage allowance ending guidance.
Primary sources
- gov.uk - Marriage allowance guidance
- gov.uk - Apply for marriage allowance online
- HMRC - Income tax rates and personal allowance 2025/26
- MoneyHelper - Marriage tax allowance
- Citizens Advice - Tax allowances for married couples
Last reviewed: May 2026.