Note: This form must be downloaded to your device in order to be filled out properly. It must be opened in Adobe Acrobat Reader.What is a Demand Letter? A demand letter is an official notice requesting money, possession of assets, or action on a legal matter. Creating a payoff letter is essential to any loan or mortgage repayment process. Our free templates and this guide can help you get started. Create a Loan Payoff Letter online and download it as a PDF or Word document. Customize and print a blank Loan Payoff Letter for free. 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.