One credit inquiry won’t impact your credit score. But if you apply for credit cards too often (two or more times a month), that will negatively impact your credit score and will lower your chances of getting approved. Every credit inquiry appears in your credit report and if there are too many of them, that will lower your credit score especially if the credit applications are declined. It is best to apply only once every six months if you are trying to build your credit. A person with good credit though can apply more frequently and still get approved.