Published: June 2026 | Fact-Checked & Audited By: David Vance, CTA FCA (Chartered Tax Advisor & Accountant)
This guide is fully updated for the 2026/27 HMRC tax year. All calculations and tax rules have been audited against official UK legislation.
Marriage Allowance is a highly effective, yet often underclaimed, tax relief granted by HMRC. It is designed to help married couples and registered civil partners reduce their joint tax bill. By allowing a lower-earning partner to transfer a fixed portion of their unused Personal Allowance to their higher-earning spouse, couples can save up to £252 per year. In this comprehensive guide, we explain the eligibility rules, walk you through the savings calculations, and detail how to backdate your claim to receive a refund payout of over £1,000.
How Marriage Allowance Works: The Math Explained
Under the Marriage Allowance scheme, the lower-earning partner transfers exactly 10% of the standard Personal Allowance to the higher-earning partner. For the 2026/27 tax year, this means transferring £1,260 of tax-free allowance. Here is how that translates into direct tax savings:
- The lower earner’s Personal Allowance is reduced by £1,260, meaning their tax-free threshold drops from £12,570 to £11,310. (To qualify, the lower earner’s annual income should ideally be below £11,310 so they don’t end up paying tax themselves).
- The higher earner’s Personal Allowance is increased by £1,260, meaning they get an extra £1,260 of tax-free income. Their tax-free threshold rises from £12,570 to £13,830.
- Since the higher earner is a basic-rate taxpayer paying 20% income tax, they save 20% on that transferred allowance: 20% of £1,260 = £252.00 in tax savings per year.
Who is Eligible to Claim?
To qualify for Marriage Allowance, you must meet all the following conditions:
- You must be legally married or in a registered civil partnership (cohabiting couples do not qualify, regardless of how long they have lived together).
- One partner must have an annual income below the Personal Allowance (£12,570) or be a non-taxpayer.
- The other partner must be a Basic Rate taxpayer. For 2026/27, this means their income is between £12,571 and £50,270 (or up to £43,662 in Scotland). If the higher earner is a higher rate or additional rate taxpayer, you are ineligible.
Backdating Your Claim: Secure a Payout of Up to £1,260+
If you met the eligibility criteria in previous years but did not claim, HMRC allows you to **backdate your Marriage Allowance claim for up to 4 previous tax years**. Because the tax saving was £252 per year for most recent tax years, backdating a claim for four years plus the current year can generate a direct cash payout of **over £1,250** sent via bank transfer or cheque from HMRC. The savings rates for previous years are:
| Tax Year | Personal Allowance | Transferred Portion (10%) | Max Tax Saving (20%) |
|---|---|---|---|
| 2026/27 (Current) | £12,570 | £1,260 | £252.00 |
| 2025/26 | £12,570 | £1,260 | £252.00 |
| 2024/25 | £12,570 | £1,260 | £252.00 |
| 2023/24 | £12,570 | £1,260 | £252.00 |
| 2022/23 | £12,570 | £1,260 | £252.00 |
To check if you qualify and calculate your potential household tax savings, use our Marriage Allowance Calculator.
Frequently Asked Questions (FAQ)
Q: What happens if the lower earner has some income?
A: You can still claim as long as the lower earner’s income is below £12,570. However, if their income is between £11,310 and £12,570, the transferred £1,260 will push their remaining allowance below their income level, meaning they will pay 20% tax on the difference. The household will still save money overall, but the net savings will be slightly lower than £252.
Q: How does HMRC apply the Marriage Allowance?
A: HMRC applies the allowance by changing the tax codes of both partners. The lower earner’s code changes to end in **N** (e.g., 1131N), indicating they have transferred allowance. The receiving partner’s code changes to end in **M** (e.g., 1383M), giving them a higher tax-free allowance. If the receiving partner is self-employed, the adjustment is calculated automatically on their Self Assessment tax return.
Q: Do we need to apply every year?
A: No. Once you submit a successful application, the Marriage Allowance transfers automatically each tax year. You only need to contact HMRC if your relationship status changes, or if both of your incomes rise above the basic rate threshold.
Q: What happens if the transferring partner dies?
A: If the transferring partner dies, their estate retains the full Personal Allowance, but the receiving partner’s tax code remains adjusted with the extra allowance for the rest of the tax year. The allowance will cease in the following tax year.