Please submit the following information with the form: Deed of Trust; Borrower(s) Signed Authorization; The Signed Loan Payoff Request Form. By including a per diem amount in the letter, the parties will not have to execute another payoff letter if the termination date.A 10 day payoff is crucial to getting your old loans paid off during a refinance. Learn how it works from start to finish. The new interest calculation applies when an FHA loan with a Note date of January 21, 2015 or after, is paid in full. It typically details the principal balance, interest due as of that date, per diem, any late fees, etc. Please provide payoff information for the above referenced mortgage. Also, please provide loan number and per diem interest.