Calculate how much Marriage Allowance you can backdate — up to 4 years for a £1,008 lump sum from HMRC.
Marriage Allowance saves £252 per year. You can backdate up to 4 previous tax years (earliest 2022/23) plus the current year, potentially claiming £1,260 total over 5 years. HMRC pays backdated amounts as a lump sum after processing your claim.
Based on 2026/27 tax rates. Marriage Allowance saves £252 per year (£1,260 × 20%). Backdating available to 2022/23. Eligibility depends on income in each year claimed.
Enter both spouses income
Enter the higher-earning spouses gross annual income and the lower-earning spouses income. Both must fall in the eligible bands.
Select how many years to backdate
Choose up to 4 years. Each eligible year adds £252 to your claim. The maximum backdated claim is £1,008 (4 years).
Confirm your marriage year
Select the year you married or entered a civil partnership. You can only claim from that point.
Apply online at gov.uk
Visit gov.uk/marriage-allowance to submit your claim. You will need your National Insurance numbers. HMRC pays backdated amounts automatically after processing.
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Disclaimer: All results are estimates for guidance only and do not constitute financial, tax or legal advice. Always consult a qualified professional.