How to follow up on an unpaid invoice

Check the facts first

Confirm the invoice was sent to the correct contact, the due date has passed, the amount is correct, and payment was not received under a different reference.

Send a friendly reminder

Assume an oversight. Include the invoice number, amount, due date, and a request for the expected payment date. Attach or link the invoice again.

Send a professional follow-up

If the client does not respond, refer to the first reminder and request a specific update. Ask whether any issue is preventing approval or payment.

Escalate carefully

A firm notice should remain factual. Follow the contract and applicable law before adding late fees, suspending work, or taking collection action.

Keep complete records

Save the invoice, reminders, responses, promised payment dates, and transaction references. This history helps resolve misunderstandings.