OIB

OIB stands for Osobni identifikacijski broj, a Croatian personal identification number issued by the Financial Administration (Porezna uprava) of the Republic of Croatia. It is a unique numeric identifier used to identify individuals and legal entities in dealings with public administration and in many private-sector activities. The OIB is an 11-digit code introduced in the late 2000s as part of reforms to unify identification numbers across government services; it is now the primary identifier in most administrative procedures, replacing or supplementing previous numbers such as the JMBG in many contexts.

The OIB is issued to Croatian citizens, residents and foreign nationals with tax or administrative obligations, and to legal entities and organizations operating in Croatia. It is used in tax reporting, social security, health insurance, employment records, banking, invoicing, and other interactions with competent authorities. The number is lifelong and generally remains unchanged, even if civil status or address changes.

Applications for an OIB can be made online through the e-Građani platform or in person at a tax administration office. For individuals, required documents typically include a valid ID; for legal entities, corporate documents are used.

Data protection and access to the OIB are regulated by Croatian law. The number is intended as a secure, unique identifier to streamline administration, improve data consistency, and facilitate official procedures, while protecting privacy by restricting unnecessary disclosure.