01 / IDENTIFYING A COMPANY
Company identifiers
What SIREN, SIRET and the NAF code mean, where to find them and how to avoid typing mistakes.
- SIRENWhat is a SIREN number and how to find itThe 9-digit format, who gets one, where it appears and how to find a company's SIREN from its name.
- SIREN · SIRETSIREN vs SIRET vs NIC: what is the difference?The company and its establishments: 9 or 14 digits, the role of the NIC and the right number for each use.
- SIRETHow to check a French SIRET numberThe 14-digit format, spotting typing mistakes and the difference between a valid SIRET and an active establishment.
- NAF CODENAF / APE code explainedWhat a code like 62.01Z means, who assigns it, what it is used for and why it cannot settle a collective agreement on its own.
02 / VAT AND COUNTRIES
VAT, Belgium and Switzerland
VAT numbers in France, Belgium and Switzerland, with the format used in each country.
- VATFrench VAT number: format and how to check itThe French, Belgian and Swiss formats, the mentions on the invoice and the check before invoicing.
- BELGIUMBelgian enterprise number: format and how to check it10 digits starting with 0 or 1, the link with Belgian VAT, establishment units and how to check it.
- SWITZERLANDSwiss UID (CHE) number and Swiss VAT numberThe CHE-123.456.789 format, the TVA, MWST or IVA suffix, VAT groups and how to check a Swiss company.
03 / INVOICING AND MONITORING
Invoice, verify and monitor your partners
The new invoicing rules, how to verify a company and the signals to watch for among your customers and suppliers.
- E-INVOICINGFrance e-invoicing 2026: why your customers' SIREN becomes mandatoryThe four new mandatory mentions, the 2026-2027 timeline and how to verify your customers' SIREN numbers.
- VERIFICATIONIs this company real? Checks before signingA six-point checklist: identifier, status, name and address, VAT, signals and sanctions lists.
- STATUSStruck-off, closed or dormant French company: how to tellStruck off, closed, dormant: the definitions, why to check before invoicing and how to be alerted to a change.
- INSOLVENCY PROCEEDINGSHow to check if a French company is in liquidationLiquidation, redressement and sauvegarde explained, the signals to watch and alerts on your customers and suppliers.
04 / CHOOSING A TOOL
Choosing an API
Concrete criteria to compare company data services before you commit.