Back to Buying a Home. Although the terms sound similar, there is a big difference between loan pre-qualification and loan pre-approval. With pre-qualification, a lender reviews information about your income, debt and assets to come up with a ballpark loan estimate. A pre-qualification is easily done via phone or online. With a pre-approval, a lender reviews your credit history in detail to determine a specific mortgage amount for which you’re approved. A pre-approval is verification that a lender is willing to loan you a certain amount of money for a home purchase.