Married couple's allowance is available where one member of the married couple or civil partnership was born before 6 April 1935. Unlike other personal allowances, the married couple's allowance is given by way of a tax reduction of the allowance at 10% at Step 6 of the income tax computation. See E1.101B and E1.102.
In 2021/22 the maximum married couple's allowance is £9,125, although this may be reduced to the minimum amount of £3,530 if the primary claimant's income exceeds the income limit (see 'Restriction of married couple's allowance — 2016/17 onwards' below)1. The allowances for earlier years are given in T6.108 and T6.110.
Note that as far as tax devolution in Scotland and Wales is concerned, the married couple's allowance is a reserved matter, which means the level of the allowance is set by the UK Government.
'Primary claimant' is not a term used in the legislation, but is useful in terms of aiding understanding of the provisions and is used in the commentary below.
The commentary below discusses the conditions that must be met for the married couple's allowance to be available, the mechanism of relief and the reduction to the allowance if the primary claimant's income exceeds the income limit. It is possible to transfer all or part of the married couple's allowance to the other spouse or civil partner, either because the primary claimant is unable to utilise the entire tax reduction or the couple would like to share the tax