Marriage Allowance Calculator

Marriage Allowance lets a married couple or civil partnership transfer £1,260 (10%) of unused Personal Allowance from the lower earner to the higher earner, reducing the higher earner’s tax bill by up to £252 for the 2025/26 tax year. To qualify, one partner must earn under the Personal Allowance (£12,570) — or have unused allowance — and the other must be a basic-rate taxpayer (income between £12,571 and £50,270 in England, Wales and Northern Ireland; or between £12,571 and £43,662 in Scotland, where qualifying bands are Starter, Basic and Intermediate). The big win is backdating. HMRC accepts fresh claims for up to 4 previous tax years, so a couple who never claimed could receive £252 × 4 = £1,008 as a lump sum, plus the £252 saving for the current year — over £1,260 in total. Apply free at gov.uk/apply-marriage-allowance; the lower earner makes the claim and HMRC adjusts both partners’ tax codes automatically. Once activated, the transfer renews every year until cancelled or eligibility ends. This calculator estimates your annual saving, models historical backdated claims, and flags whether you qualify under English/Welsh/NI or Scottish rules. It does not handle the older Married Couple’s Allowance (only for couples where one spouse was born before 6 April 1935 — worth up to £1,108 but very rare). It also does not account for income from dividends or savings interest that might push the higher earner above the basic-rate band — careful budgeting is needed if combined income is close to the threshold. Cohabiting but unmarried couples cannot claim, regardless of how long they have lived together. Marriage Allowance does not affect Universal Credit, Child Benefit (including the High Income Child Benefit Charge), or Pension Credit assessments, since the tax code change does not alter income for means-testing. If your circumstances change (divorce, bereavement, or one partner moving into the higher-rate band), notify HMRC promptly to avoid surprise tax bills.