Keeping your credit utilization ratio under 30% is one of the most important factors in maintaining a healthy credit score. The credit utilization ratio is the percentage of your available credit that you're currently using. For example, if you have a total credit limit of $10,000 and your balance is $3,000, your credit utilization is 30%.

A lower credit utilization ratio signals to lenders that you are not over-relying on credit, which is seen as a positive behavior. It is advisable to keep this ratio below 30%, and even better if it's around 10-15%. Regularly paying off your balances in full each month helps maintain a low utilization ratio and improves your credit score.