Christmas shoppers are being warned not to be enticed by 0 per cent interest credit cards flooding the market. While the number of no-interest cards have doubled in the past two years, the consequences can be high for people who do not pay off the balance in time. Analysis by financial comparison website Mozo reveals some cards revert to interest rates as high as 21 per cent. Choice’s Tom Godfrey said none of the cards should be thought of as a free ride. “While these offers sound appealing … they can be a fast track to high interest rates and very high debt that you’ll find hard to get rid of,” he said.