Rules
The lower earner (income below £12,570) transfers £1,260 of their personal allowance; the partner must pay tax at the basic rate. It cuts the partner’s tax by up to £252 a year. You can claim for up to 4 previous years.
FAQ
How much is Marriage Allowance worth?
Up to £252 a year in 2026/27.
Sources (checked 6 Nov 2026): GOV.UK Marriage Allowance.