How couples can lift their Personal Allowance to £13,830 and backdate claims

Allowance — the amount someone can earn tax-free — has been frozen at £12,570 since 2021 and is set to stay at that level until at least 2031. That freeze increases the risk of "fiscal drag", where wages rising with inflation push more people into tax bands. There is a legal way for married couples and civil partners to increase their effective tax-free income now using the Marriage Allowance, and they can backdate claims for up to four years.

You can submit a claim that covers the current tax year and up to four previous tax years if you were eligible in those years. HMRC will adjust your current tax code to give you money owed for the active year and will pay any backdated refunds by cheque. If you successfully backdate four years, the cumulative tax rebate can reach up to £1,260 (which produces the £252-per-year saving when calculated at the basic 20% rate).

Eligibility requirements are specific:

• The partner transferring unused allowance must earn less than £12,570 in the tax year. That includes people not working, on a career break, or retired with low taxable income.
• The recipient must be a basic-rate taxpayer with taxable income between £12,570 and £50,270 after deducting any pre-tax workplace pension contributions.

The transfer works only between married couples or civil partners, not between unmarried cohabitants.

You can claim Marriage Allowance online through the government website. You'll need both partners' National Insurance numbers and some forms of ID. The government provides a calculator to check eligibility before applying. HMRC will then update the recipient's tax code and process any refunds.

For the current tax year, HMRC will normally change the recipient's tax code so future pay is taxed at the reduced rate. Any amounts owed for previous eligible years are issued as cheques.

Be careful to use the official government website. The Express article warns about scam sites that look like the government portal but are imposters. Use the government's online checks and the official application route to avoid paying for a service you can do for free.

Laura Suter, director of personal finance at AJ Bell, noted that frozen allowances have pushed more people into higher tax bands and that some households overlook legitimate ways to reduce tax bills. She described Marriage Allowance as a relatively simple way to claim money back if one partner earns under the Personal Allowance and the other is a basic-rate taxpayer. She also advises checking eligibility with the government's calculator and avoiding scam websites.

If you are married or in a civil partnership and one partner has low or no taxable income while the other is a basic-rate earner, Marriage Allowance can increase your combined tax-free income to £13,830 and produce a modest cash refund. You can backdate for up to four years, but apply only through HMRC's official channels.