What are the mandatory details on an invoice?

Seller's identity (name, address, SIREN/SIRET) and client's, sequential invoice number, dates, description and quantity of services, unit price excluding tax, VAT rate and amount (or franchise note), totals excluding and including tax, payment date, late penalties and the €40 flat recovery indemnity.

What note should I include if I am under the VAT franchise?

You must include the exact note "VAT not applicable, article 293 B of the CGI". You then charge no VAT. Forgetting this note is a frequent and punishable error; it clearly indicates to the client the absence of VAT.

Does e-invoicing add details?

Yes. The reform progressively introduces new mandatory fields: client's SIREN number, type of operation (goods, services or mixed), option for VAT payment on debits, and delivery address if different. Compliant software manages them automatically.

What is the risk with a non-compliant invoice?

An incomplete invoice can be refused by the client, contested in case of non-payment, and the administration can apply fines per missing or inaccurate detail. In the e-invoicing era, a missing field can also block the automatic routing of the invoice.

Mandatory Invoice Details in 2026 (+ What's New)

An invoice is not a mere commercial document: it is a legally and fiscally valid record, framed by law. An incomplete invoice can be refused by your client, contested in case of non-payment, or penalised by the administration. Here is the exhaustive list of mandatory details in 2026, including the changes tied to e-invoicing.

Identification details

Every invoice must clearly identify both parties and the document itself:

Your details: name (or company name), address, SIREN or SIRET number. For a company, add the legal form and the capital amount;
The client's details: name and address (and, increasingly, their SIREN number for professional clients);
A unique invoice number, based on a continuous chronological sequence (no gap or duplicate);
The issue date of the invoice;
The sale or service date, if it differs from the issue date.

The service detail and amounts

The body of the invoice must precisely describe what is billed:

The precise description of each product or service;
The quantity and the unit price excluding tax;
The applicable VAT rate and amount, or the exemption note;
The total excluding tax and the total including all taxes.

VAT-franchise case: if you are under the franchise (see VAT threshold), you charge no VAT, but must include the exact note: "VAT not applicable, article 293 B of the CGI". Forgetting it is a frequent and punishable error.

Payment and recovery details

Often neglected, they are nonetheless mandatory, especially for invoices between professionals:

The payment deadline (failing which, 30 days after receipt);
The applicable late-payment penalty rate;
The mention of the flat recovery indemnity of €40 due in case of late payment between professionals;
The discount conditions for early payment (or the absence of a discount).

These details are not cosmetic: they establish your right to claim penalties in case of delay, as we explain in chasing a client who doesn't pay.

Details specific to certain activities

Depending on your trade, additional details are required:

Ten-year and professional liability insurance for building activities (insurer's name, geographic cover);
Intra-community VAT number for EU operations;
"Reverse charge" note in some subcontracting or cross-border cases (see invoicing a foreign client).

The e-invoicing novelties

The e-invoicing reform progressively introduces new mandatory details to enable automated invoice processing, notably:

the client's SIREN number;
the type of operation (delivery of goods, service provision or mixed);
the option for VAT payment on debits, where applicable;
the delivery address if it differs from the billing address.

These fields become essential in the structured format. Compliant invoicing software manages them automatically.

Key takeaway: a compliant invoice protects your right to payment and avoids penalties. In the e-invoicing era, every field counts for automatic routing.

The simplest way to forget nothing is to use invoicing software that includes all the details and updates with the regulations. See our comparison of the best invoicing software, and before the invoice, take care with your quote.

Mandatory Invoice Details in 2026 (+ What's New)