Typically, it’s best to leave your credit card accounts open, even if you’re not using them. However, there are a few valid reasons why you may want to close an account.

There’s a reason why credit experts advise against closing unused credit cards. “Canceling a credit card has the potential to reduce your score, not increase it,” Beverly Harzog, credit card expert and consumer finance analyst for U.S. News & World Report, explains.

This potential score drop often occurs because closing a credit card can impact your credit utilization ratio. The ratio measures how much of your total available credit is being used, according to your credit reports. The more available credit you use (per your reports), the worse the impact will be on your score.

Read this article for a more detailed explanation of why you might want to cancel a credit card account, and a cancellation checklist to follow should you decide to do so.