The right invoice reminder depends on one thing: how overdue the invoice is. This page gives you one strong, copyable template for each stage of the follow-up cycle, plus a link to the full library for that stage when you need more variants, subject lines or letter formats.
Which reminder to send when
The invoice reminder sequence at a glance
- Day -3 Courtesy note before the due date
- Day 0 Due-today reminder
- Day 3-6 Friendly overdue reminder
- Day 7-13 Second reminder (ask for a payment date)
- Day 14-29 Firm reminder with deadline
- Day 30+ Final notice, then formal past-due process
For the reasoning behind this timing, see the unpaid invoice follow-up schedule.
The 7 invoice reminder templates
1. Before the due date
A courtesy note a few days out. Prevents "I forgot" and surfaces disputes early.
Subject: Invoice [Invoice number] due [Original due date]
Hi [Client name], A quick note that invoice [Invoice number] for [Outstanding amount] is due on [Original due date]. Payment link: [Payment link] If anything about the invoice needs adjusting, let me know before the due date. Thanks, [Your name]
More pre-due and friendly wording: friendly payment reminder emails
2. Due today
Send the morning it falls due. Factual, short, zero pressure.
Subject: Invoice [Invoice number] is due today
Hi [Client name], Just a reminder that invoice [Invoice number] for [Outstanding amount] is due today. You can pay here: [Payment link] Thanks for keeping it on your radar. Best, [Your name]
Full due-today and day-one variants: friendly reminder templates
3. Friendly overdue reminder
A few days past due. Still assume good faith - most invoices at this stage are oversights.
Subject: Friendly reminder: invoice [Invoice number] past due
Hi [Client name], Invoice [Invoice number] for [Outstanding amount] was due on [Original due date] and looks unpaid on our side - I'm sure it just slipped through. Here's the payment link: [Payment link]. If it's already been sent, ignore this and thank you! Best, [Your name]
Day-by-day overdue wording: overdue invoice email templates
4. Second reminder
No reply to the first? Ask for a specific payment date - that is the entire upgrade.
Subject: Second reminder: invoice [Invoice number] - payment date needed
Hi [Client name], Following up on invoice [Invoice number] for [Outstanding amount], now [X] days overdue. Could you confirm your expected payment date today? Payment link: [Payment link]. If something is blocking payment, reply and I'll help resolve it. Thanks, [Your name]
Ten variants including AP and broken-promise wording: 2nd payment reminder emails
5. Firm reminder
Two or more weeks overdue with no committed date. Direct language, a deadline, and a named next step.
Subject: Invoice [Invoice number] - response required by [reply-by date]
Hi [Client name], Invoice [Invoice number] for [Outstanding amount] is now [X] days overdue and I haven't received a response to my previous reminders. Please confirm payment, or a payment date, by [reply-by date]. If I don't hear back, I'll need to move this to our formal overdue process. Payment link: [Payment link] Regards, [Your name]
Full firm-stage wording and escalation rules: firm payment reminder email
6. Final notice
The genuinely last message before escalation. Factual summary, hard deadline, cautious consequence wording.
Subject: Final notice: invoice [Invoice number]
Dear [Client name], Despite previous reminders, invoice [Invoice number] for [Outstanding amount] (due [Original due date]) remains unpaid. Please pay the full balance by [payment deadline]: [Payment link] If we do not receive payment or hear from you by that date, we may need to escalate this matter, subject to our agreement and applicable law. Contact us immediately if the invoice is disputed. Sincerely, [Your name]
Letter formats and deadline variations: final notice templates
7. Accounts-payable follow-up
When payment runs through an AP department, references matter more than tone.
Subject: Invoice [Invoice number] / PO [PO number] - past due
Hello Accounts Payable team, Invoice [Invoice number] (PO [PO number]) for [Outstanding amount] was due on [Original due date] and is unpaid. A copy is attached. Could you confirm it's approved for payment and share the scheduled payment date? Thank you, [Your name] [Phone / email]
All five AP variants with attachment checklists: accounts payable follow-up emails
What every invoice reminder must include
- Invoice number and amount
- Original due date (and days overdue, once late)
- A payment link or clear payment instructions
- One specific ask - pay now, or confirm a payment date
- A reply path for disputes or questions
Subject lines carry more weight than most people expect - a reminder that is never opened cannot get you paid. Browse 50 payment reminder subject lines grouped by the same stages as this page. And if your terms include late fees, use proper invoice late fee wording rather than improvising it in a reminder.
Send the whole sequence automatically
ChaseAI drafts all seven stages from your invoice and sends each one on schedule until you're paid.
