The mortgage payoff calculator helps you find out. A mortgage payoff letter can come in two forms.One form tells borrowers the remaining principal amount and interest they have to pay to close out the loan. Third Party Payoff Request Form. All third-party payoff requests require prior authorization. 5 ways to pay off your mortgage faster. Make bi-weekly payments. Mortgage Loan Calculator Use this calculator to determine your monthly payment and amortization schedule. ______ Copy of Payoff Statement for previous loan. Click on Payments and then click on Request Payoff.