Martin Lewis' MoneySavingExpert.com team has issued a warning to anyone with a credit card . MSE has urged people to pay off their credit card in full every month, otherwise you pay interest on the entire balance - even if you only have 1p left on your card. In the latest MSE email , the team wrote: "There's a reason it's Martin's catchphrase. With £1,000 spending debt on a credit card, if you clear the whole lot in a month, there's no interest. "Yet pay off £999.99, and you'll usually pay