Glossary

The OIN number (Organisatie Identificatienummer or Organisation Identification Number) is a unique identifier for Dutch government organisations that must be stated on e-invoices sent to the government. Without the correct OIN number the e-invoice cannot be delivered to the right government body. You can look up the OIN number of a government body via the Logius website. The OIN number is separate from the Chamber of Commerce number and VAT number.