By including a per diem amount in the letter, the parties will not have to execute another payoff letter if the termination date. Apply to Nursing Assistant, Registered Nurse, Direct Support Professional and more!You will enter an email address in the 'Copy To' section (person will receive a copy of this request). Apply to Dietary Aide, Patient Transporter, Registered Nurse and more! One of the more common required advances is called "per diem interest" or "interest due at closing. Customer: I Check the payoff letter and it does not have a per diem amount. Can substitute teachers and per diem teachers in New York City public schools join TRS? The letter is sent out after the processing of your retirement is completed. Per Diem Fees shall mean, collectively, the Per Diem Late Fee and the Per Diem Supplemental Late Fee.