Over Payment Refund Letter To Customers Template. Clearly state the decision regarding the refund.First, you need to issue a check to your customer using the Accounts Receivable account for the overpayment amount. This brief but important letter notifies a customer that he or she has overpaid you. It can serve as a very good customer relations letter. We have identified the following overpayment and are in good faith voluntarily refunding all monies collected in error. In this article, we'll show you how to write a refund request letter template that not only grabs attention but also persuades companies to act in your favor. How do I get a refund for an overpayment on my bill? If you have questions about a possible overpayment, call our Customer Service Center at 877-938-7497. The salary overpayment resulted because .