Invoice emails have one enemy: friction. Every extra sentence between your client and the amount, due date, and payment method delays payment by exactly that much reading. The templates below run from the first send through the polite reminder ladder to the final past-due escalation, plus the quote and purchase order messages that bracket the invoice itself. Copy, fill the brackets, send.
The three rules of invoice emails
- Subject line does the accounting. “Invoice #2041 from Acme Design, due Aug 15” lets the recipient file, forward, and find it without opening it. Vague subjects (“Invoice attached”) die in search two months later.
- Amount, due date, and payment method in the first two lines. Everything else is optional. Accounts-payable people process dozens of these; make yours the fast one.
- Attach the PDF and say so. Inline summaries help, but the attachment is the document of record. Name the file like the subject:
acme-invoice-2041.pdf, neverfinal_v3 (2).pdf.
1. Sending an invoice
Subject: Invoice #[number] from [your company], due [date]
Hi [name],
Please find attached invoice #[number] for [project or service], totaling [amount], due on [date].
Payment details are on the invoice; we accept [bank transfer / card / payment link]. Let me know if anything needs adjusting or if your AP team needs anything else from us.
Thanks,
[Your name]
2. Sending an invoice with a payment link
Subject: Invoice #[number], [amount] due [date], pay online
Hi [name],
Attached is invoice #[number] for [amount], due [date]. You can pay directly here: [payment link].
The PDF has full line items and our bank details if you prefer a transfer. Any questions, just reply.
Best,
[Your name]
3. The friendly reminder (a few days before due)
Optional, and quietly effective: it moves your invoice to the top of the AP pile without a hint of accusation.
Subject: Reminder: invoice #[number], [amount] due [date]
Hi [name],
A quick heads-up that invoice #[number] for [amount] is due on [date]. The original is attached again for convenience.
If it is already scheduled, ignore me. Thanks!
[Your name]
4. Payment reminder (day after due)
Assume the best; systems lose emails and approvals stall. The tone stays warm exactly once.
Subject: Invoice #[number] past due as of [date]
Hi [name],
Invoice #[number] for [amount] was due on [date] and I have not seen the payment land yet. Attaching it again in case it slipped through.
Could you let me know when it is scheduled? If it has already been sent, a payment reference would help me track it down.
Thanks,
[Your name]
5. Past due invoice, second notice (1 to 2 weeks late)
Firmer, still professional. Introduce specifics: dates, a request for a commitment, and a person.
Subject: Second notice: invoice #[number], [amount], now [X] days past due
Hi [name],
Invoice #[number] for [amount] is now [X] days past due (original due date [date]). I have attached it again along with the earlier reminders.
Please confirm a payment date this week, or let me know who in your accounts team I should follow up with directly.
Regards,
[Your name]
6. Final notice before escalation
Use only when you mean it, and only say what you will actually do.
Subject: Final notice: invoice #[number], [amount], [X] days past due
Dear [name],
Despite previous reminders on [dates], invoice #[number] for [amount] remains unpaid, now [X] days past its due date of [date].
If payment is not received by [final date], we will [pause work / apply the late fee specified in our agreement / refer the balance to collections]. I would much rather resolve this directly, so please get in touch today if there is an issue I should know about.
Regards,
[Your name]
7. Sending a quote
Subject: Quote for [project]: [amount]
Hi [name],
Thanks for the details on [project]. Attached is our quote: [amount] for [short scope summary], valid until [date].
Happy to walk through it on a call or adjust the scope either direction. If it looks right, reply with a go-ahead and we can start on [date].
Best,
[Your name]
8. Sending a purchase order
Subject: PO #[number] from [your company]: [item/service]
Hi [name],
Attached is purchase order #[number] for [item or service], totaling [amount], for delivery by [date].
Please confirm receipt and the delivery date. Invoices against this PO should reference the PO number and go to [AP email].
Thanks,
[Your name]
9. Payment received confirmation
Thirty seconds that makes the next invoice easier.
Subject: Payment received: invoice #[number]
Hi [name],
Confirming we received your payment of [amount] against invoice #[number] today. Receipt attached.
Thanks for the prompt payment; it is appreciated. Anything you need from us, just ask.
Best,
[Your name]
The reminder ladder, timed
| When | Tone | |
|---|---|---|
| Friendly reminder | 3 days before due | Light |
| First reminder | 1 day after due | Warm, assumes error |
| Second notice | 7 to 14 days late | Firm, asks for a date |
| Final notice | 21 to 30 days late | Formal, states consequence |
Consistency matters more than the exact days: clients learn quickly whether your invoices can be safely ignored, and a predictable ladder teaches them they cannot.
Stop retyping these
Invoice emails are the most repetitive email in business: the same message every month with three things changed. That is exactly what snippets exist for. CMDK stores each of these as a template in Gmail with fill-in variables for name, amount, and due date, adds read receipts so you know whether the past-due notice was opened (useful before escalating), and follow-up reminders that resurface the thread if no payment confirmation arrives.
Frequently asked questions
How do I politely ask for payment on an overdue invoice?
Assume error rather than intent: “Invoice #2041 was due on the 15th and I have not seen the payment land; could you let me know when it is scheduled?” Attach the invoice again, ask for a specific commitment (a date or a payment reference), and keep the warmth for exactly one email before firming up.
What should an invoice email say?
Invoice number, amount, due date, and payment method, within the first two lines, plus the PDF attached. The subject line should carry the number, company, and due date so accounts-payable can process it without opening it. Everything beyond that is politeness, and one sentence of it is plenty.
When should I send a payment reminder?
A friendly nudge three days before the due date, a warm reminder the day after it passes, a firm second notice at one to two weeks, and a final notice with stated consequences at three to four weeks. Predictability is the point: clients pay the invoices they know will be followed up.
Should I charge late fees on past due invoices?
Only if your contract or invoice terms specified them up front; introducing fees retroactively poisons the relationship and rarely holds up. The stronger levers are pausing work, requiring deposits on future projects, and the escalation ladder itself, which resolves most late payments before fees would apply.
Send the same invoice email every month? CMDK turns these templates into Gmail snippets with fill-in variables, plus read receipts and follow-up reminders for the ones that go quiet, for $79 a year with a 15-day free trial.
