what is a mortgage underwriter
From Wikipedia, the free encyclopedia. Mortgage underwriting is the process a lender uses to determine if the risk (especially the risk that the borrower will default) of offering a mortgage loan to a particular borrower is acceptable.isks for the lender are of three forms: interest rate risk, default risk, and prepayment risk. There is a risk to the lender that the rate on an adjustable-rate mortgage may decrease. If this is not matched by correlated decreases in rates on the lender's liabilities, profits will suffer.