Late Payment Interest Calculator for Overdue Invoices

French B2B late-payment interest: ECB rate + 10 points and €40 fee

In France, a late-paid business invoice triggers interest calculated day by day, at the rate set in your terms of sale or, failing that, the ECB rate plus 10 points (12.40% a year in the second half of 2026), plus a flat €40 recovery fee. The tool works out these amounts and drafts the reminder email.

Formula

Interest = invoice amount incl. VAT × annual rate ÷ 365 × days late. Total due = invoice + interest + €40 (box ticked by default).

Which rate to enter

Article L441-10 of the French Commercial Code first refers to the rate set in your terms of sale, which cannot be lower than three times the statutory interest rate. Without such a clause, the rate is the ECB's most recent main refinancing operation rate plus 10 points: the rate in force on 1 January applies to the first half-year, the one on 1 July to the second. The tool defaults to 12.40%, i.e. 2.40% on 1 July 2026 plus 10 points; in the first half of 2026 the rate was 12.15%.

Example

Invoice of €3,500 incl. VAT, 42 days late, 12.40%: 3,500 × 0.124 ÷ 365 × 42 = €49.94 of interest, i.e. €1.19 a day. With the €40 fee, the client owes €3,589.94.

Limits

• One rate applies to the whole period: a delay spanning two half-years needs two calculations.
• The €40 fee is due per invoice from the first day late, whatever the length of the delay; higher actual costs can be claimed with evidence.
• The rules cover business-to-business transactions; a consumer owes neither this interest nor the fee.
• The email is a reminder template, not a legal document: seek advice in a dispute.
• The note shown under the rate (about 14% to 15%) dates from 2024.

Sources and dates: French Commercial Code, Arts. L441-10 and D441-5 (€40 fee, version of Decree No. 2021-211 of 24 February 2021); ECB key rates: 2.15% since 11 June 2025, 2.40% since 17 June 2026 (checked 14/10/2026).

Frequently Asked Questions

What is the French late-payment interest rate in 2026?

If your terms of sale set no rate, it is the ECB rate plus 10 points: 12.15% for delays in the first half of 2026 (ECB at 2.15% on 1 January) and 12.40% for the second half (ECB at 2.40% on 1 July). A contractual rate cannot be lower than three times the French statutory interest rate.

How do I calculate late-payment interest on an invoice?

Multiply the amount including VAT by the annual rate, divide by 365, then multiply by the number of days late. For €10,000 paid 30 days late at 12.40%, that gives €101.92, plus the €40 recovery fee.

Is the €40 flat recovery fee due on every invoice?

Yes, it is due for each invoice paid late, from the first day and whatever the number of days. It applies between businesses and must appear on your invoices and terms of sale. If your actual recovery costs are higher, you can claim more with evidence.

Can I charge late-payment interest to a consumer?

Not the L441-10 interest or the €40 fee, which only apply between businesses. With a consumer, only statutory-rate interest can run after a formal notice, unless the contract says otherwise.

Is this tool really free?

Yes, all tools on Kristools are 100% free and accessible without registration.

Is my data protected?

Yes. All processing is performed directly and securely inside your browser. No personal data is sent to our servers.