Provide a clear explanation: Your letter should acknowledge and indicate why something happened. The letter contains key information such as the outstanding balance, accrued interest, fees, total payoff amount, and payment instructions.How do I fill this out? Filling out this file involves providing specific financial and loan details. How do I fill this out? Filling out this file involves providing specific financial and loan details. This is an example of a payoff letter used in a syndicated loan transaction. This payoff letter (including the defined terms such as Lenders,. A letter of explanation consists of short descriptions you can use to fill in the gaps in your paperwork for your underwriter. Unlike your current balance, the payoff amount includes interest owed up to the day you intend to pay off the loan.