Last updated November 6, 2026
Rules and figures from other sources checked on November 6, 2026. They change, so confirm with the source before you rely on them.
General information, not tax or legal advice. The rules depend on your country and your situation, so check anything with a tax or legal consequence with your accountant.
An overdue invoice reminder sequence is a planned series of messages that get firmer over time: a friendly nudge the day after the due date, a request for a payment date at day 7, a phone call at day 14, an escalation at day 21 and a final notice at day 30.
The point of a sequence is that you decide once, in advance. The day-7 email is much easier to send when the schedule says so than when you're wondering if it seems pushy.
What is a good schedule for overdue invoice reminders?
A good schedule for overdue invoice reminders starts the day after the due date and reaches a decision by about day 30. These day numbers are a sensible starting point rather than a legal requirement, so shorten them for small invoices and new customers.
| When | How | Tone | What you want |
|---|---|---|---|
| 3 days before due (optional) | Helpful | To catch a paperwork problem while there's time | |
| 1 day after | Assumes an oversight | Payment, or a reason | |
| 7 days after | Direct | A payment date | |
| 14 days after | Phone, then confirming email | Firm | The real reason, and a commitment |
| 21 days after | Email to someone senior | Serious | Attention from whoever can decide |
| 30 days after | Final notice in writing | Formal | Payment, or your decision on the next step |
Stop the sequence as soon as the money arrives or the customer raises a genuine query. Nothing annoys a good customer like a third reminder for an invoice they paid on Tuesday, so check your bank before each one.
Reminder before the due date
A reminder before the due date is worth sending for large invoices and first invoices to a new customer, because it finds out whether the invoice is in anyone's system while you can still fix it.
Subject: Invoice [number] falls due on [due date]
Hello [name],
A quick note that invoice [number] for [amount] falls due on [due date]. I've attached a copy to save you looking for it. If it's with someone else for approval, let me know who and I'll send it to them directly.
Thanks, [your name]
First reminder: 1 day overdue
The first overdue reminder should assume an honest oversight and make paying easy. Attach the invoice, because the customer may have lost it.
Subject: Invoice [number] was due on [due date]: [amount]
Hello [name],
Invoice [number] for [amount] was due on [due date], and I can't see a payment yet. A copy is attached. If it's already on its way, thank you, and please ignore this. If something is holding it up, reply and I'll help sort it out.
Thanks, [your name]
Second reminder: 7 days overdue
The second overdue reminder should ask for a date, because a question with a specific answer is harder to ignore than a general request to pay.
Subject: Invoice [number], 7 days overdue: please confirm a payment date
Hello [name],
Invoice [number] for [amount] was due on [due date] and is now 7 days overdue. Could you tell me the date it will be paid? If it's waiting for an approval, a purchase order or anything else from me, tell me what's missing and you'll have it today.
Thanks, [your name]
Third step: phone at 14 days, then confirm in writing
The third step should be a phone call, because email can be ignored and a question asked directly usually gets an answer. Ask for whoever approves or runs payments, and keep to three questions:
- Is invoice [number] for [amount] scheduled for payment?
- If not, what needs to happen for it to be paid?
- What date can I put down?
Then write it down the same day. A written record of what was promised is what gives the next step its force.
Subject: Following our call: invoice [number], payment by [agreed date]
Hello [name],
Thanks for your time today. As we agreed, [amount] for invoice [number] will be paid by [agreed date]. If that date changes, please let me know before it passes.
Thanks, [your name]
Fourth reminder: 21 days overdue, to someone senior
The fourth reminder should go to someone with authority over the payment, and it should set out the history so they don't have to ask.
Subject: Invoice [number], 21 days overdue: [amount]
Hello [senior name],
I'm writing to you because invoice [number] for [amount], due on [due date], is now 21 days overdue. We reminded [contact] on [dates] and spoke on [date], when payment was promised by [agreed date]. It hasn't arrived.
Please arrange payment by [date]. We're entitled to charge late payment interest and compensation on this invoice, and I'd much rather settle it without them.
Regards, [your name]
Use that second paragraph for business customers only. Private consumers aren't covered by the late payment laws, as how to charge a late fee explains.
Final notice: 30 days overdue
A final notice should state the amount, a deadline, and the one thing you'll do if the deadline passes. Write only the step you will actually take, because a threat that comes to nothing teaches the customer to wait you out.
Subject: Final notice: invoice [number], [amount], payable by [date]
Dear [name],
Invoice [number] for [amount], due on [due date], is 30 days overdue despite our reminders on [dates].
If we do not receive payment in full by [date], we will [pass the debt to a collection agency / start a court claim] without further notice, and we will claim interest and recovery costs in addition to the amount above.
If you dispute any part of this invoice, tell me in writing before that date and say why. A copy of the invoice is attached.
Regards, [your name]
Fourteen days is a common deadline. In England and Wales, the Practice Direction on Pre-Action Conduct expects a letter giving the basis of the claim, the facts and how the amount is calculated, and treats 14 days as a reasonable time to respond in a straightforward case.
What if the customer pays part or disputes part?
If the customer pays part of an invoice or disputes part of it, your reminder should ask only for what's still owed and not in question. Sending the full amount again is the most common way to turn a late payment into an argument.
Here's an invented example. An invoice totals €2,304.00: three lines of €390, €1,250 and €280 net, plus 20% VAT. The customer queries the €1,250 line.
| Net | VAT 20% | Total | |
|---|---|---|---|
| Disputed line | €1,250.00 | €250.00 | €1,500.00 |
| Undisputed lines | €670.00 | €134.00 | €804.00 |
| Invoice | €1,920.00 | €384.00 | €2,304.00 |
So you ask for €804.00 now.
Subject: Invoice [number]: your query on [item], and the undisputed amount
Hello [name],
Thanks for raising the query about [item]. I'll come back to you on it by [date]. The rest of the invoice isn't in question, so please pay [undisputed amount] by [date] while we settle the remaining [disputed amount].
Thanks, [your name]
If they've paid part without a query:
Subject: Invoice [number]: [balance] still due
Hello [name],
Thank you for the [amount paid] received on [date]. That leaves [balance] on invoice [number], which was due on [due date]. When can I expect the rest?
Thanks, [your name]
What should a payment reminder never say?
A payment reminder should never say anything you can't back up, because it may end up in front of a court or a collection agency.
- A threat you won't carry out. Once it's ignored, every later message is worth less.
- A charge you aren't owed. Statutory interest is for business customers, and a consumer contract needs its own valid term.
- The full total when part has been paid.
- Anything for an audience. Telling other people a customer owes you money can create a legal problem larger than the debt, so keep it between you and them.
What happens after the final notice?
After the final notice, you decide whether the debt is worth pursuing, and you should make that decision on the deadline rather than letting it drift. The usual options:
- Stop further work, if your contract allows it.
- Use a collection agency. They usually take a share of what they recover, so compare that with the debt.
- Make a court claim. In England and Wales you can claim online. For a cross-border EU claim up to €5,000, the European Small Claims Procedure applies in every EU country except Denmark.
- Write it off, and ask your accountant about VAT relief on the bad debt. See write-down vs write-off.
If this keeps happening, look at your terms before your reminders. Clear payment terms and deposits from new customers will do more for you than a better-worded email.
Sending payment reminders in ERPFlow
ERPFlow's reminders are manual, one click per invoice. On an overdue invoice, Send payment reminder opens a dialog with the customer's address filled in and emails a reminder with the PDF attached, saying how many days overdue it is and asking for the total or, on a partly paid invoice, the amount still due. The invoice's page then shows when the last reminder went out. Nothing sends on a schedule, so the sequence above is yours to run.
The wording of that email is fixed, in the invoice's language. It says your records show payment is overdue and asks the customer to disregard it if they've already paid, which suits the first reminder. It can't ask for a date, escalate or mention interest. For those, use Download PDF and send the templates above from your own mailbox, then add a comment on the invoice to record what you sent. Comments stay internal and never print on the PDF.
The action appears only once an invoice is overdue, so a reminder before the due date comes from your own mailbox too.
To see what needs chasing, use the invoice list's Overdue and Partially paid filters, the dashboard's Outstanding and Overdue figures, or a customer's Analytics tab. ERPFlow emails your team once, the night after a due date passes, unless notifications are turned off. It has no aged receivables report and doesn't calculate late fees.