Personal finance expert has issued an alert to anyone with a debit card with major banks including Barclays and NatWest, saying they can be ‘more dangerous’ than credit cards

15:27, 25 Jul 2026Updated 15:28, 25 Jul 2026

Martin Lewis explained that using debit instead of credit cards could, in fact, hit you in the pocket more

Martin Lewis explained that using debit instead of credit cards could, in fact, hit you in the pocket more

Martin Lewis has issued a warning to anyone holding a debit card with major banks, including HSBC, Barclays, Lloyds, NatWest, Santander UK and Nationwide, declaring them ‘more dangerous’. The personal finance guru explained that many people favour debit over credit cards due to concerns about interest rates.

However, the money-saving expert, who regularly features on ITV and the BBC, took to Facebook to caution that this approach could prove costly. He said: “Is your debit card really a secret debt card? Many people say credit cards bad, debit cards good, but actually typical high street interest rate of a credit card is 25%.

“Typical high street interest rate of an overdraft 40%. So of the two, it’s your debit card spending if you’re overdrawn that is more dangerous than a credit card, though neither of course are good. Now we have to take that honest step with the logic. Many people who have both debts will actually use money in their bank account to try and pay off the credit card. But think about that.”

He warned that the issue stems from people failing to grasp the disparity in interest rates, ultimately leaving them worse off: “What that actually means is you’re increasing the amount of more expensive debt in the overdraft to reduce the cheaper debt. You would be far better off just to make the minimum monthly repayments on the credit card and focus on clearing the overdraft.

“In fact, if you have more than one debt, the sensible move is always to list them in order of interest rate and then you take the highest interest rate. debt, which will probably be your overdraft, and you focus all your spare cash on trying to clear that while just paying the minimums on everything else.”

“Once you’ve cleared that, you focus on the second most high expensive debt, and you try and clear that and so on and so on. It’s called snowballing. And hopefully, it’ll get you debt-free a bit more quickly.”

The money-saving expert has previously highlighted a crucial rule for credit card holders — ensure the balance is cleared in full each and every month. He addressed the topic on his most recent BBC podcast, responding to a listener’s enquiry regarding the optimum approach to managing savings.

Using a £1,000 example to demonstrate his point, he said: “This is an important warning about the way that credit cards work. Imagine you’ve spent £1,000 on the credit card.”

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He continued: “If you then pay off the £1,000, so you totally clear it, there is no interest in the month. But if you were to pay off £999.99, so you’re just a penny short. You don’t pay interest on a penny for the month. You still pay interest on the entire £1,000. This is why for years my catchphrase has been pay off your credit card in full.

“The in full is important. I talk about it when it’s a credit card reward, say for getting cash back or for cheap spending on a credit card abroad. Because if you do it in full, you neuter the credit card’s ability to charge you interest. If you miss even a penny, it can still charge you a whack.”

Martin Lewis this week also gave a 3-digit number that any customer of UK of the key UK banks need to know. Anyone who uses Barclays, Lloyds, Halifax, Santander, Nationwide and other banks will need to know how to check for sure if they’re speaking to a legitimate company.

Cases of fraud in the UK have surged with criminals using AI to manipulate people and even marrying victims of romance scams to steal more money. More than four million cases in which money was lost were reported last year – the equivalent of nearly eight on average every minute, according to new figures.

The total has increased by more than one million in two years, with almost £1.3bn stolen by scammers in 2025, according to an annual report by UK Finance. Banks said fraud posed “a national security threat” given the impact on victims and the huge sums stolen by organised criminals.

Mr Lewis, a personal finance expert, said people can be conned into thinking they’re speaking to their bank – and end up divulging key information which leads to their accounts being emptied and massive debts run up. But he said there was one thing people can do to make sure they are in fact on the phone to their legitimate bank – and that’s by calling 159.

In a new video on TikTok he said: “There are three numbers you need to remember to protect yourself from scams. 159. If you dial 159 on your phone, you’ll be put through to a switchboard. It’ll ask you which bank you want to talk to. You tell it and you will be put through to your bank’s legitimate number.

“Do spread the word because there are two reasons this protects you. The first is if you get a suspicious call from someone saying it’s your bank, you can politely say to them, “You know what? I want to call through the official routes. Put the phone down and dial 159. You don’t need to look anything up.

“The second reason, there are rare times when the scammer will spoof your line. So, if you put the phone down and call back your bank and it would say, “Hello, it’s Martin’s Bank here.” And you say, “Okay, I’m through.” No. If you dial 159 and it says, “Hello, it’s Martin’s Bank.” You know it’s wrong because you should been put through to the switchboard. Protect yourself and remember 159.”