Martin Lewis warned Brits to be wary of a “dirty trick” played by mobile phone providers that sees thousands paying extra on their contracts. Issuing an alert on his television show, Martin Lewis Money Show Live, he warned customers the issue mainly occurs with mobile phone resellers, which sell network contracts at lower prices than going direct.

He cautioned: “There is a dirty trick that mobile phone firms play, and it’s from the resellers I just recommended. They’re the main ones who do this.”

After he had highlighted cheap deals with resellers, he wanted customers to see both sides of the coin so they could enter the contract fully informed.

He explained that when you go directly to the phone network, you normally pay an airtime cost, which is the tariff, and a handset cost, which you pay for a set period of time.

When the handset is paid off, which usually accounts for a chunk of the money, this cost is removed, and customers are just left to pay the airtime tariff.

However, he warned that “a lot” of resellers give customers a set price that combines the handset and the airtime, which can leave customers out of pocket further down the line.

“After two years, when you’ve paid the handset off, you keep paying the same amount. So while you could be getting a sim that is worth £6 or £7 a month, you’re paying £30 a month.”

“Note when your contract ends. Draw a line in the sand, and you need to get off it that day,” he urged the audience.

While the practice may seem unjust, the money saving expert told the audience that it is not illegal, so phone resellers are able to get away with it. 

“It may be immoral but it’s not illegal, so you’re going to struggle to get it reimbursed because they just said this is the amount you pay with us,” he explained.