Marriage Allowance Calculator 2026-27

Marriage Allowance lets a spouse or civil partner who earns less than £12,570 transfer up to £1,260 of their unused Personal Allowance to their partner. The recipient must be a basic-rate taxpayer (earning between £12,571 and £50,270). This reduces the recipient's tax bill by up to £252 per year.

The transferor's Personal Allowance drops from £12,570 to £11,310, while the recipient gains an extra £1,260 of tax-free income. The saving is always 20% of £1,260 regardless of the recipient's exact income, because the allowance is only available where the recipient pays basic rate tax.

You can backdate a claim by up to four tax years. If you have not claimed before, you could receive a lump sum of up to £1,260 for missed years. Applications are made through GOV.UK and the allowance continues automatically each year until cancelled.

What is Marriage Allowance? Allows a non-taxpayer (or low earner under £12,570) to transfer 10% of their Personal Allowance (£1,257 for 2026/27) to a basic-rate taxpayer spouse/civil partner. Recipient saves 20% × £1,257 = £252 tax per year. Backdate up to 4 years if eligible — could reclaim £1,000+. Must be legally married or in civil partnership (not just cohabiting). Apply via gov.uk/marriage-allowance.

Marriage Allowance eligibility rules. Both partners: born after 5 April 1935. The transferring partner: income under £12,570 (so doesn't use their full PA). The receiving partner: must be basic-rate taxpayer (income £12,571-£50,270 in 2026/27). NOT eligible: higher/additional rate taxpayers, Scottish intermediate rate (21%) or above. Once claimed, automatically renewed each year — but cancel if circumstances change (recipient becomes higher rate).

Married Couple's Allowance — different scheme for older couples. Different from Marriage Allowance. Only available if either spouse born BEFORE 6 April 1935 (very rare now — would be 91+ in 2026). Worth £406-£1,108/year depending on income. Tapers above £37,700 income. Will eventually disappear as eligible population dies. Confused often with Marriage Allowance — different income limits, different mechanics.

Common mistakes and backdating. Many couples miss claiming for years — you can backdate 4 tax years if eligible in those years (2022/23 onwards in 2026). £252/year × 4 = £1,008 potential refund. Common errors: claiming when both partners are higher-rate (ineligible); not cancelling when one becomes higher-rate (HMRC clawback); transferring when LP partner's income temporarily dropped (works for that year only). Use HMRC's Marriage Allowance Calculator before applying.