Marriage Tax Allowance Explained for UK Couples

Is the marriage tax allowance worth claiming? Yes, if you qualify. The marriage tax allowance lets one partner transfer 10% of their personal allowance to the other. For 2026/27 the transfer is £1,260, giving a saving of up to £252 a year.

A claim can also be backdated four tax years.

The relief exists because the UK income tax system taxes individuals rather than households. When one partner earns below the personal allowance, part of their tax-free amount simply goes unused.

Marriage allowance transfers that unused slice to a basic-rate spouse or civil partner. That stops a couple losing relief they are already entitled to.

Around two million eligible UK couples are thought to miss out each year, according to HMRC campaign messaging. Partnerships registered since April 2015 are covered, along with many that predate it.

Before applying, check that your earnings fall inside the bands HMRC sets each tax year. A successful claim can be backdated for up to four tax years if you qualified in earlier periods.

Older claims are paid as a marriage allowance rebate, often through a P800 calculation. This marriage tax allowance guide explains who can claim, how to apply, and how the saving reaches your pay packet.

Who can claim the marriage tax allowance

Eligibility follows four tests that both partners must pass. Anyone asking who can claim marriage allowance must meet all four to succeed.

You can claim a marriage allowance UK rebate if every point below applies to you and your partner:

• You are married or in a civil partnership.
• You and your partner were both born on or after 6 April 1935.
• One of you earns less than the personal allowance (£12,570 for 2026/27).
• The other pays income tax at the basic rate only (£12,571–£50,270 for 2026/27).

Couples born before 6 April 1935 fall under the older married couples allowance instead. That older relief works differently and is usually more generous.

Scottish taxpayers should check the Scottish basic-rate band, which differs from the figures above. Marriage allowance for civil partnerships otherwise follows the same rules as for married couples.

Separation, divorce, or dissolution ends your claim from the date the relationship ends. Earnings changes that push either partner out of the qualifying bands must also be reported to HMRC.

Marriage allowance eligibility depends on both incomes in each separate tax year. If one partner’s income fluctuates, HMRC may accept some years and reject others.

Keep payslips, P60s, and self-assessment records in case HMRC asks for confirmation. Those documents make it far easier to respond if a tax year is later queried.

Transfer your personal allowance to a spouse

The non-taxpayer transfers up to 10% of their unused personal allowance to their basic-rate partner. This option to transfer personal allowance to spouse or civil partner is worth £1,260 for 2026/27.

HMRC applies the change through tax codes rather than a cash payment. Once processed, the higher earner’s personal allowance rises by the transferred amount.

That increase reduces the income they pay tax on. At the 20% basic rate, a £1,260 transfer saves £252 for 2026/27.

Take Lucy and Ella, who are in a civil partnership. Lucy earns £8,000 part time and pays no income tax.

Ella earns £35,000 and pays basic-rate tax. Using 2026/27 figures, transferring £1,260 lifts Ella’s tax-free amount to £13,830 and saves them £252.

The transferring partner’s personal allowance drops accordingly — to £11,310 for 2026/27. Because they earn below that figure, they still owe no tax.

A rise in the transferor’s income above their reduced allowance may trigger a small tax bill. It is worth reviewing the arrangement each April to confirm the couple still benefits.

A marriage allowance calculator on GOV.UK can confirm the saving before you apply. Wondering how much is marriage tax allowance in your case?

That calculator takes both incomes and returns an estimate in minutes. It also flags any mismatch between the figures you enter and the qualifying bands.

How to claim marriage allowance from HMRC

The lower-earning partner makes the marriage allowance application. That person transfers part of their allowance rather than receiving it.

Have these details ready before you start:

• Both partners’ National Insurance numbers.
• Dates of birth and date of marriage or civil partnership.
• Proof of identity, such as a P60 or passport number.
• Income figures for the relevant tax year.

Once you have everything, follow these steps:

1. Sign in to your Personal Tax Account on GOV.UK or download the marriage allowance form MATCF for a postal claim.
2. Enter both partners’ details and confirm your income for the relevant tax year.
3. Submit the application — HMRC checks eligibility automatically for online claims.
4. Wait for HMRC to issue updated tax codes to both partners’ employers or pension providers.

The online route is usually the fastest. A postal MATCF form takes longer, so keep a copy of everything you send.

Current HMRC guidance suggests a new application can take several weeks to process, though turnaround varies. Once approved, the saving flows through payroll or self assessment.

Marriage allowance HMRC support is available by phone on 0300 200 3300. For full guidance before you apply, read the GOV.UK marriage allowance page .

Your marriage allowance M and N codes

HMRC signals the transfer through two tax code suffixes. Your marriage allowance tax code confirms whether you are giving or receiving the allowance.

The marriage allowance M tax code is given to the partner who receives the transfer. For 2026/27 a typical receiving code is 1383M.

That code adds the transferred amount to the standard personal allowance. For 2026/27 that means £12,570 plus £1,260, giving a tax-free total of £13,830.

The M suffix tells your employer or pension provider to apply the higher allowance through PAYE.

The marriage allowance N tax code is given to the partner transferring the allowance. For 2026/27 an example is 1131N.

That code subtracts the transferred amount from the standard personal allowance. For 2026/27 that means £12,570 minus £1,260, giving £11,310.

HMRC uses the N suffix to track the transfer at source.

Once the codes are in place, the saving is spread across the tax year through lower monthly deductions. The benefit is not paid as a lump sum.

Instead it reaches you as slightly higher take-home pay each pay period. A marriage tax allowance recipient therefore sees the saving gradually across all twelve months.

Backdate your marriage allowance claim

You can backdate marriage allowance by up to four tax years if you qualified during those periods. HMRC treats each backdated year as a separate claim.

A refund is paid for each accepted year. That means a first-time claim can cover five tax years in total — the current year plus four backdated.

The marriage allowance P800 refund amounts for recent tax years are worth up to:

• Tax year 2026/27 — £252.
• Tax year 2025/26 — £252.
• Tax year 2024/25 — £252.
• Tax year 2023/24 — £252.

Backdated claims are settled through a P800 tax calculation. The P800 shows the allowance awarded for each year and the refund due.

It also confirms how to receive payment, through bank transfer or by cheque. Most applicants now choose a bank transfer through their Personal Tax Account for speed.

Fully backdated claims can therefore be worth up to £1,260 when combined with the current year. Not every applicant qualifies for every earlier year, though.

Eligibility depends on both partners’ incomes in each specific tax year. HMRC checks each year separately and confirms which are accepted and which are rejected.

Claiming through self assessment each year

A marriage allowance claim can run through self assessment if either partner files a tax return. The rules differ depending on which partner you are in the transfer.

The transferring partner fills in the marriage allowance section of their return. A receiving partner should leave that section blank, because their tax code already reflects the transfer.

Where both file a return, the transferor should submit at least three working days first. That timing prevents HMRC from rejecting the receiver’s return before the transfer is recorded.

Once a tax code ends with M or N, ticking the marriage allowance box is no longer needed. The transfer carries forward each year automatically.

It keeps renewing until HMRC is told to stop. Reviewing the arrangement each April makes sure the transfer still benefits both of you.

Self-assessment users who claim marriage allowance 2024/25 or later years through their return can expect three adjustments from HMRC. These are: an updated PAYE code, a recalculated tax liability, and a backdated adjustment for any earlier year included.

When and how to cancel your claim

HMRC needs to be told when the allowance no longer applies. The process depends on the reason for cancelling:

• Income change — either partner can cancel through the Personal Tax Account on GOV.UK or by phoning HMRC.
• Separation or divorce — only the transferring partner can cancel, through the Personal Tax Account or by phone.
• Bereavement — handled through the Tell Us Once service, which updates HMRC along with other departments.

You can also cancel marriage allowance by calling HMRC on 0300 200 3300. Phone lines can be busy around self-assessment deadlines.

Cancellation is not immediate in every case. When a claim ends mid-year, HMRC may apply the change from the start of the next tax year.

Failing to cancel when you should can result in an underpayment demand later. Reviewing eligibility each April is the safest way to prevent demands building up over time.

If circumstances change suddenly, contact HMRC as soon as you can. Early notification reduces the chance of reclaim action further down the line.

Your next step with marriage tax allowance

Marriage tax allowance is one of the simplest reliefs in the UK tax system. Yet it reaches only a fraction of eligible couples each year.

Check whether both earnings fall inside the qualifying bands for the current tax year. Then gather your National Insurance numbers and marriage or civil partnership date.

The transferring partner makes the application online, by post, or through self assessment. Earlier qualifying tax years can be included in the same application to collect any rebate owed.

If either of you files a return, a marriage allowance self assessment claim runs through the tax return instead. The transfer keeps renewing each year until HMRC is told to stop.

Review your tax codes each April — the letters M or N confirm the transfer is still live. Reviewing also flags any change that affects eligibility for the coming year.

Keep HMRC updated if your circumstances change mid-year. Doing so avoids clawback demands and keeps your pay and tax code aligned.

Not sure whether either partner falls inside the basic-rate band? Our income tax rates guide breaks down the current thresholds.

Marriage tax allowance key takeaways

• Marriage allowance lets a non-taxpaying partner transfer 10% of their personal allowance (£1,260 for 2026/27).
• Both partners must be born on or after 6 April 1935 to qualify.
• One partner must earn less than the personal allowance and the other must pay only basic-rate tax.
• The maximum saving is £252 a year for 2026/27, delivered through updated PAYE tax codes.
• Backdating is available for up to four previous tax years and can reach £1,260 in total.
• The M tax code indicates the receiving partner and the N tax code indicates the transferor.

Check GOV.UK for the latest figures before applying, as thresholds can change each April.