A hard inquiry is made on your credit report whenever a business checks your credit report because you made an application for a credit card, loan, or other service.
When you check your credit report, you'll see both hard inquiries and soft inquiries. But it's only the hard inquiries that will impact your credit score. (Ten percent of your credit score is based on credit report inquiries.) Soft inquiries do not impact your credit score. Though all inquiries - hard inquiries and soft inquiries - remain on your credit report for two years, hard inquiries will only impact your credit score for one year.
When potential lenders check your credit report, they will only see hard inquiries.
A hard inquiry is sometimes called a hard pull.

