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 letter provides instructions on how to pay off a loan with a lump sum before the loan term ends.Learn how payoff letters work. Discover more about per diem interest—the daily interest on a loan that occurs outside of the standard repayment period. Searching for a fillable Mortgage Loan Payoff Letter Template? Use our easy editor for PDF files and fill this form out quickly. It serves as an official request to a lender, asking for a precise statement of the loan amount due, including any per diem interest. Select one loan in the main window and click Loan > Payoff Calculator on the main menu to open this window. Interest accrues on your student loan balance every day. Ensure that the county office name is noted in Section I of the voter registration application.