Martin Lewis has urged married couples to check whether they are owed as much as £1,000 from HMRC.
The Money Saving Expert has informed those who are married or in a civil partnership that they may be eligible for a` tax break of up to £250 per year - which can be backdated all the way from 2017.
This is a result of the Marriage Tax allowance, which he says many people have never claimed.
And if they haven't, that's four whole tax years' worth of money that they could be claiming back, just by filling out a quick form on the HMRC website.
Speaking on a The Martin Lewis Money Show Live, the finance journalist advised: "If you are a married couple or in a civil partnership - not common law, just living together doesn't count - and one of you is a non-taxpayer, the other is a basic 20 per cent rate taxpayer, then this person can give 10 per cent of their tax-free allowance to the other person.
"You apply online at GOV.uk and it's worth about £250 this year, but you can go back four years.
"The past years are done by cheque, this year is done by tax code change. It's very lucrative, there are over one million people who aren't claiming it."
The tax break basically means that if one person in the partnership earns less than their personal allowance (£12,570 for the tax year of 2021/22) and the other earns between £12,571 to £43,662 - making them a basic taxpayer - then the lower earner can transfer 10 per cent of their personal allowance to their other half.
This therefore reduces the tax bill that the higher earner receives considerably.
Visit GOV.uk today in order to make a claim.
Thanks to Martin once again for saving us the big bucks!
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