Which action is most likely to improve a consumer's credit utilization ratio?

Paying off existing credit card debt is the most effective action to improve a consumer's credit utilization ratio. Credit utilization is calculated by dividing the total amount of credit being used by the total credit available. When a consumer pays off existing debt, the balance on their credit cards decreases, which lowers the numerator in the credit utilization calculation without impacting the available credit limits. This results in a more favorable credit utilization ratio, which can positively influence the consumer's credit score.

In contrast, while increasing credit card limits could help if it results in a lower ratio, maintaining the same balances would not yield a significant change and thus wouldn’t effectively improve utilization. Reapplying for the same card typically leads to a hard inquiry on the consumer's report, which may temporarily affect the score without reducing overall debt. Lastly, opening new credit accounts without a clear need could dilute their credit profile and possibly lead to overspending, ultimately harming their credit health instead of improving it.