What is a SIREN number?
Discover everything you need to know about the SIREN number, the unique identifier for French businesses.
Last updated: January 2026
SIREN Definition
SIREN (Système d'Identification du Répertoire des Entreprises) is a unique 9-digit identifier assigned to each business or individual operating a business in France. It is managed by INSEE (French National Institute of Statistics and Economic Studies).
SIREN = 9 chiffres
Unique and permanent format for the entire lifetime of the business
SIREN Number Composition
The SIREN number consists of 9 digits divided into three groups of three digits for easier reading:
- The first 8 digits are assigned sequentially by INSEE
- The 9th digit is a control key calculated using the Luhn algorithm
- The number has no geographical or sectoral significance
SIREN Example
This number uniquely identifies the business
Difference between SIREN and SIRET
| SIREN | SIRET | |
|---|---|---|
| Length | 9 digits | 14 digits |
| Identifies | The business | The establishment |
| Uniqueness | One per business | One per establishment |
| Example | 732 829 320 | 732 829 320 00074 |
The SIRET is simply the SIREN followed by the NIC (5 digits) to identify each establishment.
SIREN Number Attribution
The SIREN number is automatically assigned when the business is registered:
Who receives a SIREN?
- • Sole proprietorships
- • Companies (SARL, SAS, SA, etc.)
- • Associations
- • Self-employed individuals
When is it assigned?
When the business is created, at the time of registration with the Trade Register or the Business Directory. It remains permanent even if the business activity or location changes.
What is the SIREN number used for?
- Uniquely identify the business in all its administrative procedures
- Search for public information about a business (via INSEE, Infogreffe, etc.)
- Verify the legal existence of a business before working with it
- Appear on all official business documents
- Serve as the basis for generating SIRET numbers for each establishment
Want to learn more about SIRET?
The SIRET is the identification number for establishments. Discover how it is composed and how it differs from SIREN.
Frequently Asked Questions about SIREN
No, each company (legal or natural person) has only one unique SIREN number. However, if it has multiple establishments, each will have a different SIRET (same SIREN + different NIC).
No, the SIREN is permanent and remains the same throughout the company's life, regardless of changes in name, activity or headquarters.
The time to obtain a SIREN varies: 1-3 days for an auto-entrepreneur, about 1 week for a sole proprietorship, and 1-2 weeks for a company (SARL, SAS, etc.).
The SIREN consists of 9 digits: the first 8 are assigned sequentially by INSEE with no particular meaning, and the 9th is a check key calculated by the Luhn algorithm to detect input errors.
No, a SIREN number is never reassigned. Even after the definitive closure of a company, the SIREN remains in the SIRENE database marked as "closed" and will never be reused for another entity.
Important notice
Official Sources
This content is based on official French government sources:
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