Applying for a new credit card while looking for a house could hurt your chance of getting a mortgage with a competitive interest rate.

A credit card issuer would check your credit report in a hard inquiry. A new card would lower the average age of your accounts. Both could hurt your credit score.

Even a small drop in your credit score could affect your interest rate and add thousands to the overall cost of the loan. The mortgage lender could deny your application altogether.

Apply for a new credit card at least three to six months before applying for a mortgage or, ideally, after you close on a house.