Subject: Invoice [#1234] for $[amount] is due [date]
Hi [First name], A quick heads-up that invoice [#1234] for $[amount] is due on [date]. I have attached it in case it is easier to find here than in the original email. If it is already scheduled, thank you, and no reply needed. If anything on it needs a fix before it can be approved, let me know and I will turn it around today. Payment details: [link or remittance details] Thanks, [Your name]
A reminder sent a few days before the due date is the cheapest late-payment prevention there is. It puts the invoice back at the top of the client's inbox at the moment their AP is deciding what goes in the next payment run, and it surfaces paperwork problems (a missing PO, a wrong entity) while there is still time to fix them before the due date.
Keep it short and make it easy to ignore if everything is fine. The goal is not a reply; it is a payment on time.
What to change
- The subject line. Invoice number, amount, and due date. That is what gets it opened and what makes it findable when forwarded to AP.
- The attachment. Attach the invoice PDF every time. Assume the original is buried.
- Payment details. A link if you have one, or the ACH details. Paying should take less effort than replying.
What to avoid
- Sending it on every invoice if you invoice dozens a week; save it for the ones that matter.
- Asking for a reply. This email should be ignorable when everything is on track.
- Anything that sounds like you expect it to be late.
Common questions
Should you send a reminder before an invoice is due?
Yes, for invoices large enough that a late payment would matter. A short note three business days before the due date reduces late payments noticeably and surfaces paperwork problems while there is still time to fix them.
How early should a pre-due reminder go out?
Two to three business days before the due date. Earlier and it is forgotten again; later and the client's payment run may already be set.
What if the client already scheduled the payment?
The template says 'no reply needed' for exactly that case. The reminder costs them nothing to ignore.