The Marriage Allowance lets the lower earner transfer £1,260 of their Personal Allowance (the amount you do not pay income tax on) to their spouse or civil partner. This reduces their tax by up to £252 in the tax year 2022-2023. This is just over 10% of the standard £12,570 Personal Allowance in the 2022-23 tax year.
The partner who earns more will get £1,260 added to their standard Personal Allowance. To be eligible, the lower earners income must normally be less than the standard Personal Allowance. The higher earners salary must fall within the basic rate tax band, which in 2022-23 is between £12,570 and £50,270. Scottish income tax has different bands and rates. You cannot claim Marriage Allowance if you're living together and not in a marriage or civil partnership.
The person who earns the least should apply. You can apply online through the government website or call 0300 200 3300. HMRC will give the higher earner the Personal Allowance that has been transferred to them either by changing their tax code or when they send their Self-Assessment tax return. It can take up to 2 months for HMRC to change your tax code. If your application is successful, changes to your Personal Allowance will be backdated to the start of the tax year (6 April). You can backdate your claim to include any tax year since 5 April 2018 that you were eligible for Marriage Allowance. Your partners tax bill will be reduced depending on the Personal Allowance rate for the years you're backdating. The Personal Allowance will transfer to the higher earner automatically every year until you cancel Marriage Allowance.
If your marriage or civil partnership ends then either of you can cancel Marriage Allowance. However, if your income changes and you're no longer eligible for Marriage Allowance, the person who made the claim must cancel.
If your partner died after 2016, and you meet the criteria for Marriage Allowance, you can still apply for the benefit. You'll be applying for a backdate of the benefit up to four years. To apply for Marriage Allowance if your partner has died, call Marriage Allowance enquiries on 0300 200 3300.