A loan commitment letter is a letter provided by a mortgage lender that indicates a borrower has passed their underwriting guidelines and that they are willing to offer the borrower a home loan.

A loan commitment letter is an indication that the buyer’s home loan has been approved. It is different from a lender pre-qualification letter, which indicates that a lender has reviewed some preliminary information provided by the borrower verbally, but has not yet reviewed financial documentation. It is also different from a pre-approval letter, which indicates that the lender has reviewed financial documents and is awaiting final review and appraisal for a particular home purchase.