Dear [Customer's Name], We hope this letter finds you well. We would like to bring to your attention that there is an outstanding payment on your account. As per our records, the payment for [Service/Product] provided on [Date] has not been received. We understand that situations may arise leading to inadvertent delays in payment. However, it is important to settle outstanding balances promptly to ensure the smooth continuation of our business relationship. The payment amount due is $[Amount]. We kindly request that you settle this amount within [Number of Days] days from the date of this letter. Please make the payment by the due date to avoid any inconvenience or unnecessary late payment charges. To facilitate a quick and convenient payment process, we offer multiple payment options. You can choose to pay via check, wire transfer, online banking, or by visiting our office during business hours. Should you require any assistance or have any queries regarding the payment process, our customer support team is always available to help. Please find attached a copy of the invoice for your reference. Your prompt attention to this matter is highly appreciated. We value our business relationship with you and hope to continue our partnership for many years to come. In the event that you have already made the payment, please accept our apologies and kindly disregard this reminder. If you encounter any issues or discrepancies regarding the payment, please do not hesitate to reach out to us immediately. We will gladly investigate and resolve any concerns. Thank you for your attention to this matter and your continued support. We look forward to receiving your payment soon. Should you have any questions or concerns, please feel free to contact our accounts department at [Phone Number] or [Email Address]. Yours sincerely, [Your Name] [Your Position] [Your Company Name]