Marriage Allowance lets you transfer £1,260 of your Personal Allowance to your spouse or civil partner — saving them up to £252 per year in income tax. It is free to apply for and one of the most commonly missed tax reliefs in the UK, with HMRC estimating that over 2 million eligible couples have not claimed.
Who is eligible?
You can claim Marriage Allowance if all of the following apply:
- You are married or in a civil partnership.
- The lower-earning partner has income below the Personal Allowance (£12,570) — meaning they do not pay income tax.
- The higher-earning partner is a basic rate taxpayer (income between £12,571 and £50,270). They must not pay Higher Rate or Additional Rate tax.
If the higher earner pays 40% or 45% tax, Marriage Allowance does not apply — but they may benefit from other strategies like pension contributions to reduce their bill.
How much do you save?
The lower earner transfers £1,260 of their Personal Allowance to the higher earner. This means:
- The lower earner's Personal Allowance reduces from £12,570 to £11,310. Since they earn less than £12,570 anyway, this has no effect on their tax.
- The higher earner's Personal Allowance increases from £12,570 to £13,830. They save tax on an extra £1,260 of income at 20% = £252 per year.
The saving is modest but completely free and ongoing — once set up, it applies automatically each year until you cancel it.
How to apply
The lower-earning partner applies online through HMRC's Marriage Allowance service (GOV.UK). You will need both partners' National Insurance numbers. The transfer is applied to the higher earner's tax code — you will see their code change from 1257L to 1383L.
You can also backdate a claim for up to 4 previous tax years. If you have been eligible since 2022/23 and never claimed, you could receive a lump-sum refund of up to £1,008 (4 years × £252).
When to cancel
You should cancel Marriage Allowance if:
- The lower earner starts earning above £12,570 — they will now owe tax on the £1,260 they have transferred away.
- The higher earner moves into the Higher Rate band (above £50,270) — they are no longer eligible.
- You separate, divorce, or dissolve your civil partnership.
Cancellation is done through the same HMRC online service. If you forget to cancel after separation, the allowance continues to be applied — check your tax code.
Common mistakes
- Applying the wrong way round. The lower earner transfers TO the higher earner. If you apply and you are the higher earner, HMRC will reduce your allowance instead of increasing it.
- Not backdating. Many people only apply for the current year and miss out on refunds from previous years.
- Confusing it with Married Couple's Allowance. That is a different, older relief for couples where one partner was born before 6 April 1935. Most couples under 90 should claim Marriage Allowance instead.
See the effect on your take-home pay
Use the income tax calculator to see how a higher Personal Allowance affects your monthly take-home. Enter the higher earner's salary and set a custom tax code of 1383L to see the Marriage Allowance effect in action.