Yes, you can damage your excellent credit score. Unfortunately, damaging your credit score is much easier than improving it, so you’ll always want to be careful with how you use your credit cards and other types of loans. Your credit activity will be reported to all three of the major credit bureaus, and most lenders and credit card issuers are fast to report negative behavior. Stay responsible, pay off your debts, don’t carry a balance, don’t max out your cards.