Use this free UK marriage allowance tax calculator to estimate whether a couple may qualify and how much tax you could save in a year. Enter each partner’s annual taxable income, select the tax year, and review the eligibility breakdown instantly.
Marriage Allowance Calculator
Estimate only. Assumes standard UK (non-Scottish) income tax bands, no pension tapering, and no special tax adjustments.
What is Marriage Allowance?
Marriage Allowance is a UK tax benefit that lets a lower-earning spouse or civil partner transfer a fixed part of their Personal Allowance to their partner. If eligible, this can reduce the higher earner’s tax bill.
In most recent years, the transfer amount has been £1,260, which can create a tax reduction of up to £252 per year (20% of £1,260). The exact effect depends on both partners’ income levels.
How this marriage allowance tax calculator works
- It identifies the lower earner as the potential transferor.
- It checks if the transferor is within the Personal Allowance for the selected year.
- It checks whether the receiving partner appears to be a basic-rate taxpayer.
- It estimates the recipient’s tax reduction and any possible tax increase for the transferor after the allowance transfer.
- It shows an estimated net household effect.
Eligibility checklist (simplified)
- You must be married or in a civil partnership.
- The partner transferring allowance usually needs income at or below the Personal Allowance.
- The receiving partner generally needs to pay income tax at the basic rate (not higher/additional rate).
- Both partners must be born after 6 April 1935 to use Marriage Allowance (older couples may be eligible for Married Couple’s Allowance instead).
Example scenarios
1) Full benefit case
If one partner earns £10,000 and the other earns £30,000, the couple will often receive close to the full tax reduction for that tax year, because the recipient has enough tax liability to use it.
2) Partial benefit case
If the recipient earns just above the Personal Allowance, they might not owe enough tax to use the full reduction. In that case, the saving can be lower than the headline maximum.
3) Not eligible case
If the higher earner is above the basic-rate limit (for example, in higher-rate tax territory), Marriage Allowance is usually not available.
How to claim Marriage Allowance
You can usually apply online through HMRC. The lower earner normally makes the application. Once approved, HMRC adjusts tax codes so the benefit is applied through payroll or tax calculation.
- Have both National Insurance numbers ready.
- Confirm income estimates for the tax year.
- Apply via your Government Gateway account.
Can you backdate a claim?
Yes, many couples can backdate claims for up to four previous tax years (subject to HMRC rules and deadlines). That can result in a useful lump-sum refund if you were eligible but never claimed.
Important notes before you rely on the estimate
- This page provides educational calculations, not personal tax advice.
- Scottish income tax bands are different and may affect accuracy.
- Other factors (benefits, savings income, adjusted net income, and coding adjustments) can change final HMRC results.
FAQ
Is Marriage Allowance the same as Married Couple’s Allowance?
No. They are different reliefs with different eligibility criteria.
Can unmarried couples claim?
No, this relief is for married couples and civil partners only.
How much can I save?
Up to the annual maximum set for the tax year, commonly around £252 in recent years, though your actual saving may be lower.