Ensure all necessary financial information is accurately provided. Thinking of taking on a mortgage from a family member?Then you'll likely look into a mortgage assumption agreement. THIS MORTGAGE ASSUMPTION AGREEMENT (hereinafter referred to as the. "Agreement") made and entered into as of this ______(1)______ day of ______(2). " Access the Loan Assumption Request Form. A mortgage assumption agreement is basically you coming in and saying sign this paperwork I'm still responsible for the mortgage. A loan assumption agreement allows them to understand what is expected from them and ensures that they are aware of their rights and legal responsibilities.