What Is the Marriage Allowance and How to Claim It?

Photo by Sandy Millar on Unsplash

The Marriage Allowance is one of the few tax breaks in the UK that requires you to actively claim it — and because it’s not automatic, a significant number of eligible couples miss out on it year after year. If you’re married or in a civil partnership and one of you earns below the Personal Allowance, you may be entitled to claim up to £252 back in tax per year, plus backdated claims stretching back four tax years.

This guide explains exactly who qualifies, how it works, and how to claim it in under ten minutes.

What Is the Marriage Allowance?

The Marriage Allowance lets one partner transfer 10% of their Personal Allowance to their spouse or civil partner. In 2026/27, the Personal Allowance is £12,570, so the transferable amount is £1,257.

The receiving partner then has a higher effective allowance against which their income is taxed. Since this reduces taxable income at the basic rate, the tax saving is 20% of £1,257 = £251.40, rounded to £252 per year.

This isn’t a huge amount — but it’s free money that requires roughly 10 minutes to claim once and then applies automatically each year.

Who Qualifies?

Both partners must meet specific conditions:

The lower earner (the transferor):
– Must earn below the Personal Allowance (£12,570 in 2026/27)
– This includes those who have no income at all, work part-time, are self-employed with low profits, or receive income only from savings or investments below the threshold
– Cannot be paying income tax at any rate other than 0% (i.e., must be a non-taxpayer)

The higher earner (the recipient):
– Must be a basic rate taxpayer — earning between £12,570 and £50,270 in England, Wales, and Northern Ireland (Scottish rates differ slightly)
– Cannot be a higher rate or additional rate taxpayer

Both partners must be:
– Married or in a civil partnership (not cohabiting — living together without marriage or civil partnership does not qualify)

If these conditions are met, the lower earner applies to transfer their allowance to their partner.

How Much Can You Claim in Total?

HMRC allows backdated claims for up to four tax years. If you’ve been eligible since your marriage or civil partnership and never claimed, you may be entitled to up to £1,260 as a lump sum, plus the current year’s allowance going forward.

The four-year backdating window means you should claim as soon as you’re eligible, as you permanently lose the right to each year’s allowance once the window closes.

How It Affects Tax Codes

When the Marriage Allowance is approved, HMRC changes the tax codes of both partners:

• The transferor receives a tax code ending in N (meaning they’ve transferred 10% of their allowance)
• The recipient receives a tax code ending in M (meaning they’ve received 10% of their partner’s allowance)

You’ll see these changes on payslips, P60s, and in your Personal Tax Account online. If your tax code shows M or N and you didn’t apply for Marriage Allowance, contact HMRC to investigate.

How to Claim

The process is straightforward and is done entirely online:

1. Go to Marriage Allowance on GOV.UK
2. The lower-earning partner applies — not the higher earner
3. You’ll need: National Insurance numbers for both partners, and confirmation of your marriage/civil partnership date
4. Select the tax years you want to backdate the claim to
5. HMRC processes the claim and adjusts tax codes

The whole process typically takes under 10 minutes. HMRC usually processes backdated claims as a repayment — either a cheque to the higher earner or an adjustment to their tax code.

If you complete a Self Assessment tax return: the Marriage Allowance is claimed through Self Assessment instead of the GOV.UK form. Make sure it’s included in your return.

If your circumstances change: if either partner’s income changes so that they no longer meet the eligibility conditions — for example, the lower earner returns to work and exceeds £12,570 — you must cancel the Marriage Allowance via GOV.UK. You’ll receive a tax code update removing the M or N suffix.

Common Questions

Does it matter how long we’ve been married?
No. Eligibility is based on income, not the length of the marriage. You can apply at any point once both conditions are met.

Can same-sex couples claim?
Yes — the Marriage Allowance applies to both marriage and civil partnership, regardless of gender.

What if my partner is self-employed?
Eligibility is based on taxable income from all sources, not employment income specifically. A self-employed person with profits below £12,570 may well be eligible to transfer their allowance.

Can both partners transfer to each other?
No — the transfer only goes from the lower earner to the higher earner. If both partners earn below the Personal Allowance, neither pays tax and the Marriage Allowance is irrelevant. If both earn above it, neither can transfer.

Does it affect pension credits or benefits?
The Marriage Allowance does not affect entitlement to means-tested benefits. It only affects income tax — not Universal Credit, Pension Credit, or other income-related benefits.

According to HMRC’s Marriage Allowance statistics, millions of eligible couples have still not claimed the allowance, suggesting significant unclaimed money sitting with HMRC.

The GOV.UK Marriage Allowance eligibility checker takes about two minutes to use and confirms your eligibility before you submit a claim.

Conclusion

The Marriage Allowance is a genuine, simple, uncomplicated tax saving that a significant proportion of eligible couples have never claimed.

• Eligible couples save £252 per year — small but cumulative, and automatic once claimed
• Backdated claims cover up to four tax years — potentially a £1,000+ lump sum for couples who’ve been eligible and not claimed
• The lower-earning partner applies — takes about 10 minutes at GOV.UK
• Watch for the N and M tax codes on payslips to confirm the allowance is in place
• Cancel it if circumstances change — if the lower earner’s income rises above £12,570, the allowance must be removed

Next read: Want to understand your full tax picture? Read our guide on what is a tax code and how to check yours UK: /what-is-a-tax-code-and-how-to-check-yours-uk