Most unpaid invoices get paid when you ask for them correctly. A strong email is not aggressive — it is specific, documented, and structured so the client feels the urgency without feeling attacked.
Template 1: Firm reminder (7 days overdue)
Subject: Invoice #[number] — 7 days overdue
“Hi [Name],
I wanted to follow up on invoice #[number] for $[amount], which was due on [date]. I sent an initial reminder on [date] but haven’t heard back.
Could you let me know when I can expect payment, or if there is an issue with the invoice I should be aware of?
I’ve attached the invoice again for reference.
Thanks, [Your name]”
This template works because it references your prior contact (documenting the follow-up sequence) while leaving room for an innocent explanation.
Template 2: Strong notice (14 days overdue)
Subject: Invoice #[number] — 14 days overdue, action required
“Hi [Name],
Invoice #[number] for $[amount] is now 14 days past its due date of [date]. I’ve sent two reminders without response.
Per our agreement, a late fee of [X]% applies to balances unpaid beyond [X] days. I’d prefer to resolve this without applying the fee.
Please arrange payment within 48 hours, or contact me to discuss.
Invoice attached.
[Your name]”
Mentioning the late fee by reference to “our agreement” signals you have documentation — which prompts faster action than simply stating you’re going to charge extra.
Template 3: Final demand (21 days overdue)
Subject: Final notice — Invoice #[number], $[amount] outstanding
“Hi [Name],
This is a final notice regarding invoice #[number] for $[amount] plus accumulated late fees, now [X] days overdue.
I have sent multiple reminders beginning on [date] without receiving payment or a substantive response.
If payment — or a confirmed payment arrangement — is not received by [specific date], I will proceed with [small claims / collections / referral to my attorney].
I have maintained a full record of all correspondence related to this invoice.
I hope we can resolve this directly.
[Your name]“
Template 4: Payment plan offer (for clients in difficulty)
“Hi [Name],
I understand things can get complicated. If the full amount of $[amount] is difficult right now, I’m open to a structured payment plan.
A possible option: $[X] on [date] and $[X] on [date], for the full balance.
If this works, please confirm by reply and I’ll send a revised invoice reflecting the plan.
[Your name]“
What to do after the final notice
If a final demand goes unanswered for seven days, move to action. File in small claims court, engage a collections agency, or send a formal attorney’s letter. At this point, email follow-up has run its course.
Waco makes it easier to get to this point with a clean record. Every time a client opens your invoice, it is timestamped. Every email you send as part of a Waco follow-up sequence is logged. That paper trail is exactly what you need if the matter moves to court.
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