What Is the Marriage Allowance and How to Claim It
The marriage allowance is a tax relief that could save you £252 a year if you're in a couple where one partner earns below the personal allowance threshold. If you're not using your full personal allowance, you're leaving money on the table — and the government won't tell you about it.
In this guide, we'll walk through what the marriage allowance is, who qualifies, how much you can actually save, and exactly how to claim it (including how to backdate claims up to four years).
What Is the Marriage Allowance?
The marriage allowance lets you transfer the unused portion of your personal allowance to your spouse or civil partner.
Here's how it works: the UK personal allowance for 2025/26 is £12,570 — that's the amount of income you can earn tax-free. If you earn less than £12,570, you're not using all of it. That unused allowance is wasted unless you transfer it.
The marriage allowance lets your partner claim up to 10% of the personal allowance — that's £1,260 — to reduce their tax bill. If they're a basic rate taxpayer (earning between £12,570 and £50,270), that saves them £252 per year (20% of £1,260).
Example: Sarah earns £8,000 a year and doesn't pay any tax. Her husband Dan earns £45,000 and pays tax at 20%. Sarah can transfer £1,260 of her unused personal allowance to Dan. That reduces Dan's taxable income from £45,000 to £43,740. He saves £252 in tax that year. Sarah's income is still £8,000 and tax-free; the transfer doesn't affect her.
It sounds small, but claimed correctly and backdated, it's a straightforward win. And it takes about 5 minutes to apply.
Who Can Claim Marriage Allowance?
You can claim marriage allowance if:
- You're married or in a civil partnership. Marriage allowance is only for couples who are legally married or have a registered civil partnership. Cohabiting couples, sadly, don't qualify.
- One partner earns less than the personal allowance. The lower earner must have a taxable income below £12,570 (2025/26). This includes salary, pensions, and other taxable income.
- The higher earner is a basic rate taxpayer. The partner with the higher income must earn between £12,570 and £50,270. If they're a higher rate taxpayer (earning over £50,270), marriage allowance won't save them anything — they'd benefit from other reliefs instead.
- Neither of you is claiming other allowances. You can't transfer marriage allowance if the lower earner has already claimed a blind person's allowance, marriage allowance (from someone else), or receives certain benefits like Working Tax Credit. You also can't claim it if you're a student with a Student Loan. Check the official HMRC guidance to confirm your eligibility.
How Much Will You Actually Save?
The saving depends on the higher earner's tax rate.
For a basic rate taxpayer (20%):
- You transfer £1,260 of personal allowance
- That's £1,260 × 20% = £252 per year
Example: Priya earns £11,000. Her wife Aisha earns £38,000. Priya transfers £1,260 to Aisha.
- Priya's tax: £0 (still below the personal allowance)
- Aisha's taxable income drops from £38,000 to £36,740
- Aisha's tax drops by £252
Over 3 years, that's £756. Over 5 years, £1,260. It's not a fortune, but it's real money for doing nothing, and you can claim it retroactively.
If the higher earner pays higher rate tax (40%):
- Marriage allowance doesn't help. They'd get more benefit from pension contributions or ISA investing. See our guide on the tax-free personal allowance for other strategies.
How to Claim Marriage Allowance
The process is simple, but the details matter. You can claim online, via post, or by phone. Most people go online because it's faster.
Step 1: Check eligibility
Go to www.gov.uk/marriage-allowance and use their eligibility checker. Have both partners' National Insurance numbers and this year's income figures ready.
Step 2: The lower earner applies
Only the lower-earning partner can claim. You'll need:
- Your National Insurance number
- Your partner's National Insurance number
- Your approximate income for this tax year
- Your partner's approximate income for this tax year
- A Government Gateway login (you'll create one if you don't have it)
You'll complete the claim online at gov.uk/marriage-allowance/how-to-apply. The form takes about 5 minutes.
Step 3: Your partner confirms
HMRC will email your partner asking them to confirm the claim within 30 days. They log into their Government Gateway account and agree. Without confirmation, the claim won't go through.
Step 4: HMRC processes it
Once both partners have confirmed, HMRC processes the claim. The tax relief usually starts the tax year after you apply, or the month after you apply (depending on how quickly HMRC processes it). You'll get a letter confirming.
Step 5: Check your coding notice
Once the claim is approved, your partner's tax code will change to include the marriage allowance transfer. For example, a tax code might change from 1257L to 1334L. The extra digits reflect the additional personal allowance they can now use.
Can You Claim Backdated Marriage Allowance?
Yes — and this is where marriage allowance gets even better.
You can claim backdated relief up to four years back, as long as you were eligible in those years. So if you're applying in 2026, you can claim relief back to 2022/23, 2023/24, 2024/25, and 2025/26.
Example: It's May 2026. You've just realized marriage allowance exists. Your partner earned £35,000 and you earned £9,000 in all the past four tax years. You claim now. HMRC will calculate relief for:
- 2022/23: £252
- 2023/24: £252
- 2024/25: £252
- 2025/26: £252
That's £1,008 in total relief over four years, potentially as a refund or reduction in next year's tax bill.
To claim backdated relief, apply in the same way as above, but select the tax years you want to include. HMRC will sort out the payments — usually via a bank transfer or adjustment to your tax code.
When Does Marriage Allowance End?
Marriage allowance stops automatically if:
- One of you earns more than £12,570 (the lower earner's income threshold)
- The higher earner's income exceeds £50,270 (they move to higher rate tax)
- You divorce or dissolve your civil partnership
- One of you dies
- You claim another allowance that's incompatible with marriage allowance
You should tell HMRC straight away if your circumstances change. If you don't report, they may overpay relief and ask you to repay it. Use your Government Gateway account or call HMRC Marriage Allowance to update.
If you've claimed marriage allowance but your circumstances have now changed (maybe you got a pay rise or switched jobs), you can cancel it at any time. There's no penalty — you just stop getting the relief from the next tax year.
Marriage Allowance and Other Tax Reliefs
Marriage allowance works alongside other tax allowances and reliefs, but it doesn't replace them.
Personal allowance: Marriage allowance uses part of the lower earner's personal allowance to boost the higher earner's. The personal allowance is still £12,570 for each of you; marriage allowance just redistributes some of it.
ISA allowance: Completely separate. You each get your own ISA allowance of £20,000 per tax year. Marriage allowance doesn't affect it. See our guide on ISAs and how to maximise your allowance for more.
Pension contributions: If the lower earner makes pension contributions, those count against their income for marriage allowance purposes. Example: Sarah earns £10,000 in salary and contributes £2,000 to her pension. Her taxable income is £8,000. Her unused personal allowance is £4,570 (£12,570 − £8,000). She can only transfer up to £1,260 via marriage allowance; the rest is just unused and doesn't benefit anyone.
Working from home relief: Completely separate — you can claim both. See how to claim working from home tax relief for details.
Dividend allowance: If you're a director with a dividend tax allowance, marriage allowance doesn't interfere. Same with annual investment allowance for business equipment — all independent.
The key point: marriage allowance is a straightforward transfer of spare personal allowance. It doesn't interact awkwardly with other reliefs; they sit alongside each other.
Common Questions About Marriage Allowance
Q: Does marriage allowance affect my benefits?
A: No. Benefits are calculated based on your actual income, not your taxable income after marriage allowance. Transferring allowance doesn't change whether you qualify for means-tested benefits.
Q: What if my income varies month-to-month?
A: HMRC uses your approximate annual income when you apply. If you're self-employed and income varies, give your best estimate based on last year's tax return or a forecast. If you overestimate, HMRC will adjust the relief; if you underestimate and you drift above the thresholds mid-year, contact them to cancel.
Q: Can we have marriage allowance and still file separate tax returns?
A: Yes. Marriage allowance is claimed separately from your tax return. Each of you files your own return as usual; marriage allowance just adjusts your coding notice and tax code.
Q: What if one of us is not a UK resident?
A: Marriage allowance is generally only available if both partners are UK residents. If one of you works abroad or is a non-resident, you likely can't claim. Check with HMRC directly.
Q: Do we claim marriage allowance if we're in a same-sex marriage or civil partnership?
A: Yes, absolutely. Marriage allowance applies to all legally married couples and registered civil partnerships, regardless of gender or sex. The rules are exactly the same.
Q: What happens to marriage allowance if we get divorced?
A: It stops at the end of the tax year in which the divorce becomes final. You need to tell HMRC to cancel it. Any relief for the partial year is calculated pro-rata.
Q: Can we switch who claims it each year?
A: No. If you claim marriage allowance, the lower earner claims and transfers to the higher earner. You can't swap it around year to year. However, if circumstances change (income swaps over), the partner with the lower income would claim next time.
Q: I've just started a new job. Can I still claim marriage allowance?
A: Yes, but base your claim on your expected annual income for the full tax year, not just the months you've worked. HMRC allows for changes if circumstances change mid-year.
Ready to Claim?
Marriage allowance is one of the simplest tax reliefs to claim and one of the most commonly missed. If you're in a couple where one of you earns under £12,570 and the other earns under £50,270, spending 5 minutes to apply could save you £252 a year, potentially backdated to four years ago.
Start your claim at gov.uk/marriage-allowance/how-to-apply.
And if you need to work out how a pay rise, job change, or dividend income would affect your eligibility, our calculators can help you model the numbers before you apply.