Unpaid invoice reminder: e-mail templates and late-payment penalties

An unpaid invoice does not settle itself. A reminder sent at the right time, in the right tone, is often enough. This article sets out the steps, four message templates and the French rules that let you claim penalties and an indemnity. The generator above calculates the delay, the penalties and the indemnity for your invoice, then prepares the message. Nothing is sent: you copy the text into your own e-mail.

These rules apply to businesses invoicing customers in France under French law. The examples use fictional figures.

The reminder steps

The timings below are common business practice, not deadlines set by law. Adapt them to each customer relationship.

1. Before the due date. Show the payment date on the invoice, with the payment terms: the period, the penalty rate and the amount of the indemnity (see below). A reminder a few days before the due date prevents many delays.
2. The first reminder, courteous. A few days after the due date: a friendly e-mail that assumes a simple oversight. No figures at this stage.
3. The second reminder. One to two weeks later, if nothing has been received. You restate the amount, the delay and the penalties.
4. The third reminder, the last before formal notice. You state clearly what comes next, without excessive threats.
5. Formal notice (mise en demeure). A letter sent by registered post with acknowledgement of receipt, setting a payment deadline. The French Civil Code states that the debtor is placed in default “by a summons or an equivalent sufficient demand” (article 1344). A registered letter proves the date of receipt, which an e-mail does not always do.
6. Payment order (injonction de payer). If the formal notice has no effect, you can ask a court for a payment order. For a debt between businesses, the request goes to the president of the commercial court (tribunal de commerce) where the debtor has its registered office. Outside Alsace-Moselle, the creditor pays a court fee of €33.47 within 15 days of the request (service-public.fr).

Message templates

These texts match the generator. Replace the brackets with your details, or let the generator fill them in.

1. First, courteous reminder

Subject: Invoice [invoice number]: payment reminder

Hello,

Unless we have missed it, invoice [invoice number] for [amount] incl. VAT, due on [due date], has not yet been paid. A copy is attached to this message.

It may simply have slipped through. If you have already paid, please disregard this reminder. Otherwise, could you let us know when payment is planned?

I remain available for any question.

Kind regards, [your name]

2. Second reminder

Subject: Invoice [invoice number] is still unpaid

Hello,

Our previous message has gone unanswered. Invoice [invoice number] for [amount] incl. VAT, due on [due date], is still unpaid today, [number of days] days after its due date.

Please pay it within [payment deadline]. If something stands in the way of payment (a dispute, an error in the amount, a missing document), let us know and we will deal with it quickly.

As French law provides, late-payment penalties of [penalty amount] (rate of [rate]) and a fixed recovery indemnity of €40 are due. The total to pay is [total].

Kind regards, [your name]

3. Third reminder, last before formal notice

Subject: Final reminder before formal notice: invoice [invoice number]

Hello,

Despite our previous messages, invoice [invoice number] for [amount] incl. VAT, due on [due date], remains unpaid: [number of days] days late as of today.

If [total] is not received within [payment deadline], we will send you a formal notice by registered letter with acknowledgement of receipt. To avoid this step, you can pay now or call us to agree on a payment plan.

Late-payment penalties ([penalty amount]) and the €40 fixed indemnity are due, and they continue to accrue until payment.

Kind regards, [your name]

4. Formal notice letter

Subject: Formal notice (mise en demeure): invoice [invoice number]

Dear Sir or Madam,

Unless we have missed it, invoice [invoice number] for [amount] incl. VAT, due on [due date], has not been paid despite our reminders.

We hereby formally call on you to pay [total] within [deadline] of receiving this letter, made up of:

• [amount] incl. VAT for the invoice;
• [penalty amount] of late-payment penalties (rate of [rate], [number of days] days late on the date of this letter);
• €40 fixed indemnity for recovery costs.

Late-payment penalties continue to accrue until payment. Payment is made by bank transfer to [IBAN].

If payment is not received within this period, we will take the appropriate recovery action, including an application for a payment order.

Yours faithfully, [your name]

Send the formal notice by registered letter with acknowledgement of receipt, and keep the acknowledgement. Unlike a simple reminder, it sets a deadline and states what happens next.

Penalties and indemnity under French law

Between businesses, late-payment penalties are due from the day after the payment date, without any reminder being needed (article L441-10). Their rate is the one written in your terms of sale or on the invoice. If none is written, it is the European Central Bank’s main refinancing rate plus 10 percentage points. That rate is 2.65% since 16 September 2026 (ECB), so the default penalty rate is 12.65% a year.

A written rate cannot be lower than three times the legal interest rate. For the second half of 2026, that legal rate is 2.75% for professional receivables (order of 26 June 2026), so the floor is 8.25% a year.

The calculation is:

Penalties = amount incl. VAT × annual rate × days late ÷ 365

Take a fictional invoice of €4,800 incl. VAT, paid 21 days after its due date, at the default rate of 12.65%: 4,800 × 12.65% × 21 ÷ 365 = €34.93 in penalties. Add the €40 indemnity: €74.93 in total, on top of the €4,800.

The fixed recovery indemnity is owed automatically by any business in late payment (article L441-10). Its amount is set at €40 by article D441-5. It is due once for each invoice paid late (Service-public.fr), from the first day, without a reminder. It is not multiplied by the number of days.

What to write on your invoices

To claim penalties and the indemnity without argument, your payment terms specify them (article L441-10, II) and your invoices must mention them: the late-payment penalty rate and the €40 fixed indemnity are mandatory invoice mentions (article L441-9). On each invoice, show:

• the issue date and the due date, or the agreed payment period;
• the late-payment penalty rate, with the statement that penalties are due without a reminder;
• the amount of the €40 fixed indemnity;
• your bank details (IBAN) for transfers;
• a unique, sequential invoice number, and the purchase order reference if your customer uses one.

Keep a record of every reminder: date, method of sending, any reply. If the matter goes to court, that file is what counts.

Payment periods are themselves capped: no more than 60 days after the invoice date, or 45 days end of month when the contract expressly provides for it. Our article on working capital shows what each day of payment delay costs in cash.

Automating reminders

A forgotten reminder costs as much as a badly written one. The safest approach is to schedule reminders from your list of unpaid invoices: each message goes out on the planned date, at the right level, and you approve it before it is sent. It is a repetitive task well suited to automation, and we build it on your real cases. To see what this looks like, read our AI and automation offer.

Frequently asked questions

How many reminders before a formal notice?

French law sets no number. A common practice is two or three written reminders, then a formal notice. The right number depends on the customer and the amount. What matters is that each reminder is dated and kept.

Can I send reminders by e-mail?

Yes, for reminders. An e-mail leaves a dated trace and can be sent in one click. For the formal notice, a registered letter with acknowledgement of receipt remains the usual form, because it proves the date of receipt.

How long should I wait between reminders?

There is no legal period. One to two weeks is common practice. You can shorten it for a customer who usually pays late, and lengthen it when a dispute is in progress.

Can I claim penalties if the contract does not mention them?

Yes. Unless another rate is written, the rate is the ECB rate plus 10 points. Penalties are due without a reminder, as is the €40 indemnity (article L441-10).