You should never close your credit cards, even if they have a zero balance on them because the credit cards and the time it has been established provides history on your credit report. Closing a credit card that has a balance on it lowers your total debt to available balance ratio which can in turn affect your credit score. If you have multiple cards, try to pay down the one with the highest interest rate first but NEVER close your credit card because you will never be able to re-establish the existing history of the trade line.

However recent studies by credit reporting agencies show having too many open credit accounts will negatively affect your credit as well, the key to developing good credit is one of balance having a reasonable amount of credit to go along with your financial lifestyle. Also noted is that credit lenders are shying away from basing their approvals and rates on credit score alone and beginning to look at the bigger picture such as payment history, length of credit etc.