Martin Lewis is urging the millions of people in the UK who receive a regular payslip to check it straight away as they could have lost out on thousands.
The Money Saving Expert founder was live in Liverpool on Tuesday for an end-of-series special of his Money Show Live on ITV.
The finance guru said people should check their wage slips as soon as possible before an April deadline as they could lose out on thousands of pounds if they don't.
He told his audience, and ITV viewers, that if the deadline is missed and it turns out your tax code was wrong, you won't be able to reclaim the money and some people could lose thousands of pounds that they're owed.
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