Balance transfer credit cards offer a low or zero-percent introductory rate – but only for a limited time. Suppose you fail to pay off your balance during the pre-set time frame. In that case, you’ll be stuck with paying the much higher default rate that kicks in once the discounted-rate period ends. As a result, you should make a concerted effort to settle your debt within this window of opportunity. In addition, balance transfers come with a fee (1% to 3% of the transfer amount), which the card provider immediately adds on top of your transfer amount.