Credit card companies typically report your credit card balance on your statement closing date. Since a low credit utilization ratio (the percentage of your available credit you use) has a positive impact on your credit score, it can help your credit score to pay the majority of your balances off.  If you are going to pay them off in order to improve your credit score, you would ideally want to do so at least 45 days prior to applying for a loan so that the credit reporting agencies have time to update the new balances.   If you don’t have at least 45 days, you may be able to send the new balance information to the bureaus directly to have them update your balances faster.