1. Check the invoice first
Match the name, project reference, invoice number, billing period, quantities, rates, tax line if applicable, and amount due to your records. Remove placeholders and use a filename the client can identify.
- Correct recipient
- Complete line items
- Agreed due date and terms
- Supporting documents attached when required
2. Choose a delivery channel
Email is common, but a client portal, shared system, payment link, or paper copy may be required by the contract. Use the customer's preferred address and do not put sensitive information in an unsecured subject line.
If the customer has a required billing portal or purchase-order process, follow that process before sending a duplicate email.
3. Write a useful message and keep the record
Subject: “Invoice INV-1042 for kitchen repair — due 30 September”. Body: “Hi Jordan, attached is invoice INV-1042 for the work completed 1–15 September. The amount due is $860 under our agreed terms. Please reply if a line needs clarification.” This is an example, not a delivery promise.
Save the sent file, message, date, and any supporting documents. If the due date passes, use a factual reminder that points to the invoice and agreement.
4. Handle special billing moments
A deposit, milestone, progress claim, or final invoice should name the event that makes it due. If you resend an invoice, identify the original number and explain why it is being resent. For a past-due workflow, see the related guide rather than changing the original invoice silently.