Invoice Email Template: What to Write When You Send an Invoice
Copy-paste invoice email templates: sending an invoice, a friendly reminder, an overdue notice, a final notice and a thank-you after payment. Plus subject lines that get opened.
Subject lines that get opened
- Invoice 2026-014 from [Your Business] — due 15 Apr
- [Client name], your invoice for the kitchen remodel
- Reminder: invoice 2026-014 due Friday
- Overdue: invoice 2026-014 (due 15 Apr)
- Paid — thank you, [Client name]
1. Sending the invoice
Hi [Name],
Thanks again for having us out on [date]. Attached is invoice [number] for [short description], total [amount], due [date].
You can pay by [Zelle/Venmo/card link/check]. Let me know if anything on it needs a tweak.
Best, [Your name], [Business], [phone]
2. Friendly reminder (2–3 days before due)
Hi [Name], a quick reminder that invoice [number] for [amount] is due on [date]. The PDF is attached again in case it got buried. Thanks!
3. Overdue notice (1 week after due)
Hi [Name], invoice [number] for [amount] was due on [date] and I haven't seen the payment yet. If it has already gone out, please ignore this. Otherwise you can pay by [methods]. Thank you.
4. Final notice (30 days after due)
Hi [Name], invoice [number] for [amount] is now 30 days overdue. Per the terms on the invoice a late fee of [amount] applies from [date]. Please arrange payment by [date] or let me know if there is an issue I should know about.
5. Thank you after payment
Hi [Name], payment received for invoice [number] — thank you. Receipt attached. It was a pleasure working with you; if you know anyone who needs [service], I'd appreciate the referral.
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Questions
Should I attach the invoice or paste it in the email?
Attach the PDF and put the amount, due date and payment method in the email body. The client should be able to pay from the email without opening the attachment.
How many reminders are normal?
Three: a friendly one before due, one a week after, and a final notice at 30 days. Then a phone call.
Is it rude to send a reminder before the due date?
No. A short reminder two or three days before is standard and most clients appreciate it; it is what their own vendors do.
Free invoice templates