France · INSEE Sirene
French SIRET Number Checker
Check a French SIRET number for correct format and check digit, and confirm the establishment in the Sirene register — with its name and whether it is still open.
What is a SIRET number?
A SIRET is the 14-digit number INSEE gives each establishment of a French business: the company’s 9-digit SIREN followed by a 5-digit NIC — for example 775 670 417 00051 for LVMH’s head office. A business has one SIREN but a SIRET for every site, and the SIRET changes when a site moves.
French SIRET format
Fourteen digits: the SIREN, a 4-digit establishment number and a check digit.
(the company)
number
Example: 775 670 417 00051 (LVMH, head office). Spaces are presentation only.
- 14 digits: SIREN (9) + NIC (5). The NIC has no meaning — it does not tell you whether a site is the head office.
- Check digit: The full 14 digits pass a Luhn check. A La Poste SIRET (SIREN 356 000 000) that fails it is still valid if its digits sum to a multiple of 5.
- Changes on moving: Every change of establishment address produces a new SIRET; the old one is closed in the register.
- Where it appears: On payslips, in public-sector invoicing through Chorus Pro, and in many official forms. Commercial invoices require the SIREN.
How to check a SIRET number
- 1 Find the SIRET on a payslip, a public-sector invoice or the business’s Kbis or avis de situation.
- 2 Enter all 14 digits above. The checker validates the format and check digit, then confirms the establishment in the Sirene register.
- 3 Check the returned name and status — a closed establishment keeps its SIRET in the register.
- 4 Want to run the official lookups yourself? Our SIRET verification guide walks through them step by step.
Frequently Asked Questions
What is the difference between SIREN and SIRET?
The SIREN (9 digits) identifies the company; the SIRET (14 digits) identifies each of its establishments — the 9 SIREN digits followed by a 5-digit NIC. One head office and two shops means 1 SIREN and 3 SIRETs. Check a SIREN number.
How many digits is a SIRET and what do they mean?
14. The first 9 are the SIREN. The last 5 are the NIC: a 4-digit establishment number and a check digit. The NIC says nothing about the activity or location, and the head office is not necessarily 00001.
Is the SIRET or the SIREN required on an invoice?
Invoices must show the seller’s SIREN, and the e-invoicing reform adds the customer’s SIREN. The SIREN is the first 9 digits of the SIRET. Public-sector invoices sent through Chorus Pro are addressed to the buyer’s SIRET.
Does a SIRET change when a business moves?
Yes. A SIRET changes whenever the address of the company or of one of its establishments changes, while the SIREN stays the same — Danone’s head-office SIRET changed in August 2025 when it moved within Paris.
How do I check that a SIRET is valid? (Comment vérifier un SIRET ?)
Enter it in the checker on this page: it validates the 14 digits and check digit, then confirms the establishment in the Sirene register with its name and status. For the official lookup routes, see our SIRET verification guide.
Why does a La Poste SIRET fail the usual check?
La Poste establishments (SIREN 356 000 000) are the documented exception: a La Poste SIRET that fails the Luhn check is still valid if its 14 digits add up to a multiple of 5. INSEE’s validation tooling accepts them, and so does the checker on this page.
Last reviewed: , against official sources.
Verify French establishments at scale
Check SIRET and SIREN numbers against the Sirene register in one API call — with name and status.