The store partnered with New Jersey-based First Choice Bank and 10 other lenders to offer mortgages.
Members under the program can sign up for loans online and the rates, closing costs and terms are listed up front. Costco claims that it can save homeowners up to $5,000 over the typical life of the loan.
The Costco website also allows various lenders to provide quotes to loan shoppers.
About 10,000 people have already taken out their home loans with Costco. The retailer also offers health and auto insurance and eventually plans to offer student loans.