Searching for a fillable Mortgage Loan Payoff Letter Template? Use our easy editor for PDF files and fill this form out quickly.By including a per diem amount in the letter, the parties will not have to execute another payoff letter if the termination date. Select one loan in the main window and click Loan > Payoff Calculator on the main menu to open this window. You must request a mortgage payoff letter from your lender. It typically details the principal balance, interest due as of that date, per diem, any late fees, etc. You must request a mortgage payoff letter from your lender. It also often gives information on how best to deliver the payoff funds, etc. If you have the funds to pay off an installment loan early, request a payoff letter from your lender. Discover more about per diem interest—the daily interest on a loan that occurs outside of the standard repayment period.