When you’re given a store credit card, you may be offered a promotional financing offer. This is done to entice you to buy and to get you to take the card. For example, you may be in the market for a new TV and be offered a card that gives you 0 percent interest as long as you pay off the balance of the card in the next 12 months.

If you take the card, you may assume it’s a chance to buy and forget about it for a while. You could buy a $2,000 entertainment system and just decide you’ll deal with it in a year. By then, you think you’ll have some extra money, so you might as well get the system now. You don’t have to do anything for a year, right?

Sort of. In many cases, these promotional deals still mean you have to make minimum payments. You need to get the card, activate it, and then send in those smaller payments on time. They may be a few percent of the total due.

On top of that, if you want to pay the whole amount off on time, you may really need to send in more than the minimum. For instance, the minimum may just be $20, but you’re only going to get through $240 over the course of 12 months. To pay it all off on time, you either need to send in more or have that lump sum waiting to go in with your final payment.

All credit card offers are different, and this is merely one example of how some cards work. However, it shows how important it is to really understand what you’re agreeing to so that you don’t accidentally end up with more debt than you anticipated.

Source: Synchrony Bank, “Understanding Minimum Payments,” accessed March 02, 2017