Martin Lewis has issued a warning to 'millions' of people who have been given the wrong tax code on their payslip - with time running out to reclaim tax you're owed back.

In April, the deadline to claim back any overpaid tax for the year 2020-21 will pass, because you can only claim for backdated tax overpayments for four financial years. Come April, that year will be too far back, Martin Lewis told his audience on the latest episode of The Money Show Live on Tuesday night.. Your tax code, which can be found on your payslip, shows how much Personal Allowance you get given for the tax year by HMRC - how much you can earn before you have to pay tax. It also has other information, such as a letter which can change depending on other factors such as emergency tax codes.

For example, the most common code is 1257L. This means that you get £12,570 before you have to pay any tax on the amount above that threshold. But if, for example, you underpaid tax or HMRC needed to deduct more tax from you due to earning too much savings interest, the following year your new code might be changed to 1100L, which means you lost £1,570 from your tax-free allowance.

The problem is, a lot of tax codes on payslips are not correct and it could mean you're overpaying tax or you overpaid tax in a previous tax year. With just weeks until April, there is not much time left to reclaim any overpaid tax for the 2020-21 tax year, Martin warned.

Martin Lewis said: "Millions of them are wrong, and the crucial thing here: it is not HMRC's responsibility, it is not your employer's responsibility, it is YOUR responsibility to ensure it's right.

"Now you may have overpaid hundreds of thousands of pounds in 2020-21, this is your last opportunity to check if that's right.

"So go online to a tax calculator, they'll tell you what it meant, and check if it is right, cos if not you're gonna miss the opportunity to get the money back if you overpaid.

"If you underpaid, funnily enough, they have longer to come back and reclaim the tax back off you.

"That's the way it works."

The Martin Lewis Money Show Live is still available to watch via ITVX catchup service.