May 19, 2009
[Name of Recipient]
[City, State ZIP Code]
Dear [Name of Recipient]:
We have received your check in the amount of $[Amount] as payment for Invoice [Invoice Number]. Please note that you were only supposed to pay $[Amount], and therefore overpaid $[Amount]. [Optional add reason why customer might have overpaid. Otherwise remove i.e. It appears that you did not apply the 5% discount for paying the invoice within 10 days.]
We have issued a credit of $[Amount] to your account for the overpayment. This credit will be reflected in your next invoice/statement.
Should you have any questions or if I can be of any further assistance, please do not hesitate to contact me.
[Title if any or delete if none]