By including a per diem amount in the letter, the parties will not have to execute another payoff letter if the termination date. A payoff agreement is an informal contract in which a creditor agrees to accept the balance of a debt owed as full payment.Please provide payoff information for the above referenced mortgage. Also, please provide loan number and per diem interest. Searching for a fillable Mortgage Loan Payoff Letter Template? Use our easy editor for PDF files and fill this form out quickly. ➢ Assumable mortgage, subject to lender or VA approval of the assumer's credit. ➢ Right to prepay loan without penalty.