What Is the SIRET Number?
The SIRET number is a unique 14-digit identifier assigned to every business establishment in France. It is issued by INSEE (Institut National de la Statistique et des Etudes Economiques) and registered in the SIRENE directory, which is the official registry of all French businesses and their establishments.
The SIRET number is composed of two parts:
- SIREN (9 digits): Identifies the legal entity (company) itself. Every company in France has exactly one SIREN number, regardless of how many locations it operates.
- NIC (5 digits): The Numero Interne de Classement identifies the specific establishment (physical location, branch, or office) within that company.
For example, a SIRET like 12345678901234 breaks down as SIREN 123456789 + NIC 01234.
Why the SIRET Matters for E-Invoicing
The SIRET number plays a central role in the French electronic invoicing ecosystem:
Mandatory Invoice Field
Under French commercial law and the upcoming 2026 reform, the SIRET of both the seller and the buyer must appear on every invoice. For Factur-X documents, this information is embedded in the CII XML data, ensuring machine-readability.
PPF Directory Registration
When registering on the PPF (Portail Public de Facturation), businesses are identified by their SIRET. The PPF directory maps each SIRET to the company’s chosen invoicing channel (PPF direct or a specific PDP). This means the SIRET is essentially the routing key in the e-invoicing network.
SIRENE API Lookup
The SIRENE directory provides a public API that allows verification and lookup of business information using the SIRET number. Compliance tools can use this API to:
- Validate that a SIRET is active and not ceased.
- Retrieve the official business name, legal form, and address.
- Confirm the establishment’s activity code (APE/NAF).
This automation is crucial for enriching invoice data with accurate legal information.
SIRET vs. SIREN vs. TVA Intracommunautaire
Understanding the different French business identifiers:
| Identifier | Digits | Scope | Use |
|---|---|---|---|
| SIREN | 9 | Legal entity (company) | Company-level identification |
| SIRET | 14 | Establishment (location) | Invoice-level identification, PPF routing |
| TVA Intra | 13 (FR + 11) | VAT registration | EU cross-border transactions, VAT reporting |
For e-invoicing purposes, the SIRET is the primary identifier because France requires establishment-level granularity, not just company-level.
Obtaining and Managing SIRET Numbers
A SIRET number is automatically assigned when:
- A new business is registered in France (via the guichet unique at INPI).
- An existing business opens a new establishment.
- A business transfers its headquarters.
Businesses must keep their SIRET information up to date. Changes in address, legal status, or activity code should be declared to the relevant authorities, as outdated information can cause invoice validation errors in the PPF.
SIRET in Practice for SaaS and E-Commerce
For businesses using billing platforms like Stripe or e-commerce solutions like PrestaShop, the SIRET number must be:
- Stored in your system: Your own SIRET must be configured in your invoicing setup so it appears on every outgoing invoice.
- Collected from B2B clients: When invoicing another French business, you need their SIRET to generate a compliant invoice. Automated SIRENE lookups can help validate and enrich this data.
- Validated regularly: SIRET numbers can become inactive if a business ceases operations or an establishment closes. Periodic validation ensures your invoices will not be rejected.
Practical Implications
The SIRET is more than just an administrative number. In the context of the e-invoicing reform, it becomes a critical data point that determines invoice routing, validation, and compliance. Ensuring accurate SIRET data for your business and your clients is one of the foundational steps in preparing for the 2026 mandate. Automation tools that integrate SIRENE lookups directly into the invoicing workflow can significantly reduce the risk of errors and rejections by the DGFiP.