OIB: what the Croatian personal identification number is and how you get it

As soon as you acquire Croatian citizenship, almost every form you fill in will have a field marked "OIB". This is the Croatian osobni identifikacijski broj (personal identification number) – the permanent identifier under which Croatian authorities keep you in their records. This article explains what the OIB is, who assigns it, how a new Croatian citizen living in Serbia gets one, how to find out your number, and what the OIB is not. Where the official sources give no answer, we say so plainly.

What the OIB is

Under Article 2 of the Personal Identification Number Act (Zakon o osobnom identifikacijskom broju, Official Gazette NN 60/08), the OIB is a "permanent identification mark" that public bodies use in official records, in their day-to-day work and when exchanging data. It has been in use since 1 January 2009.

It has 11 digits: ten are chosen at random and carry no information about you, and the eleventh is a check digit (Article 3 of the Act).
It is unique and never changes: the Act describes it as unique, non-descriptive, unchangeable and non-repeatable (Article 4). The Croatian Tax Administration (Porezna uprava) states that an OIB, once assigned, does not change regardless of a change of first name, surname or address.
It is assigned by the Ministry of Finance – Tax Administration, ex officio, on the basis of data from the bodies that keep official records (Article 8 of the Act).

The Tax Administration also states that the OIB is the tax number for taxation purposes – so Croatia has no separate "tax number" alongside it.

OIB, MBG and the Serbian JMBG are not the same thing

In older Croatian documents you may come across the MBG (matični broj građana, the former citizen's registration number). The Tax Administration states that the MBG stopped being issued on 4 February 2023 and that the OIB has fully replaced it. The key difference, according to the official explanation, is that the OIB is not a "descriptive" number like the MBG: nothing about the person can be read from it.

The Serbian JMBG is a number from Serbian records, while the OIB is assigned by the Croatian Tax Administration – one does not replace the other. On Croatian forms you enter your OIB.

How a Croatian citizen gets an OIB

Under the regulations, a Croatian citizen does not file a separate application: the OIB is assigned ex officio, on the basis of registration. Article 8(2) of the Act provides that Croatian citizens are assigned an OIB on the basis of data on their entry in the register of births (matica rođenih), and those who are not entered in the register of births on the basis of data on their entry in the register of citizens (knjiga državljana). The Tax Administration sums it up like this: the number is assigned upon entry of the birth in the register of births or entry of citizenship in the register of citizens, and an OIB is received by "Croatian citizens by birth or by acquiring Croatian citizenship".

The Ordinance on the Personal Identification Number (Pravilnik o osobnom identifikacijskom broju) expressly lists "entry of the acquisition of Croatian citizenship or subsequent entry in the register of citizens" as a "first entry". The body that makes the first entry sends the data to the Tax Administration (Article 7 of the Ordinance), and the OIB certificate is, under Article 12 of the Ordinance, delivered through that body. Article 10 of the Act allows up to 30 days from the assignment of the number for the certificate to be delivered.

The Tax Administration also states that a foreign individual who "is applying for Croatian citizenship" needs an OIB and that in this case the person deals with the Ministry of the Interior, not the Tax Administration. It is therefore possible that your number was already assigned during the procedure; the official pages do not explain how this works when the application is filed through a consulate.

In practice this means you do not request the number yourself – you receive it along with the registration. If nobody has told you your OIB after you were entered in the register of citizens, ask the consular office through which you filed your application. The whole procedure is described on the Process page.

If you do not have an OIB: application to the Tax Administration

For cases where no number has been assigned, Article 13 of the Act provides that the Tax Administration will assign it subsequently. The Tax Administration states that Croatian citizens who live abroad and have no OIB submit:

the form "Zahtjev za određivanjem i dodjeljivanjem OIB-a" (application for an OIB);
an identity document (Croatian identity card or passport);
a domovnica (certificate of citizenship) – for citizens who acquired citizenship before 1 January 2009 and were not given an OIB;
documentation whose content matches the documents entered in the civil registers of the Republic of Croatia;
a power of attorney, if needed.

The form can be downloaded from the Tax Administration website. According to the instructions on the form itself, it is submitted to the locally competent Tax Administration branch office; for a Croatian citizen with no registered residence in Croatia, the competent office is the one for the place where the "reason for monitoring" arose, and if competence cannot be determined – the Tax Administration, Zagreb Regional Office. The Ordinance (Article 14) provides for submission in person, together with documents confirming the data you state.

Through a consulate? On the website of the Ministry of Foreign and European Affairs, some missions publish a form called "Zahtjev za izdavanje OIB-a" (application for the issue of an OIB) among their consular forms (for example the Embassy in Australia), and the Consulate General in Mississauga states that the assignment of an OIB can be requested through it. We found no such explicit statement for Belgrade or Subotica, so before you go, ask the consular office whether it accepts the application and what to bring. Appointments are booked on the Croatian consular portal (konzularniportal.mvep.hr) (see our guide to booking an appointment).

For questions about the OIB, the Tax Administration refers people to the competent branch office or to oib@porezna-uprava.hr. It mentions submitting the application by e-mail only as an exception for pensioners living abroad who receive a Croatian pension.

What it costs

Nothing. Article 54 of the Ordinance states that no fee is charged for determining and assigning the personal identification number or for issuing the certificate to the holder. If someone charges you for "issuing an OIB", you are paying for their service, not a state fee. For other costs, see the Costs page.

The OIB certificate and how to find out your number

The assigned number is recorded in an OIB certificate (potvrda o OIB-u), which under Article 9 of the Act has the status of a public document. The Tax Administration specifies that it issues the certificate and that the certificate does not serve as an identity document but as proof of the OIB – you still show your passport or identity card alongside it.

If you do not have the certificate to hand, there are several ways to find out your number:

in your passport – the Travel Documents Act provides that the passport form contains a space for the OIB;
through the service "Uvid u podatke o osobnom identifikacijskom broju" (OIB data look-up) on the Tax Administration website;
by requesting a certificate (uvjerenje) from the Tax Administration;
through the "Moj OIB" (My OIB) service in the e-Građani (e-Citizens) system, which shows your data from the OIB register (e-Građani is accessed with a vjerodajnica, i.e. an electronic login credential).

What you need the OIB for

Under Article 6 of the Act, you are required to state your OIB on all applications and submissions addressed to public bodies and other users of the number, and in payment transactions. When listing the cases in which a foreign individual needs an OIB, the Tax Administration specifically mentions the following situations – the same ones in which you will be asked for the number:

acquiring real estate or securities;
opening a bank account;
founding a company;
entry in any official register of persons and property in Croatia;
becoming a taxpayer.

What exactly a particular bank or employer requires is something to ask them. The list of papers for the citizenship application is on the Documents page.

Does having an OIB mean you pay tax in Croatia

In the OIB regulations we reviewed, we found no provision that ties a tax liability to simply holding the number. By law the OIB is an identifier, and the Tax Administration expressly states that there are entries in official records through which a foreign person "does not become a taxpayer" (its examples are opening a bank account and founding a company).

The Tax Administration explains that tax residence is determined under the General Tax Act (Opći porezni zakon) and double taxation treaties, starting from domicile and habitual abode. According to the provision the Tax Administration quotes, a domicile for tax purposes exists where the taxpayer owns or possesses a dwelling continuously for at least 183 days in one or two calendar years, and a habitual abode means a stay of at least 183 days.

This is only the general framework, not tax advice. If you acquire real estate or income in Croatia, or register a residence there, ask the Tax Administration or a licensed tax adviser about your obligations.

Common misunderstandings

"I have an OIB, so I have citizenship." No. Foreigners also receive an OIB when a "reason for monitoring" arises – for example by buying real estate or opening an account. Citizenship is proven by a valid identity card, passport or domovnica, not by an OIB certificate.
"I will get a new OIB after I become a citizen." No. If you were given an OIB earlier as a foreigner, it stays the same when you acquire citizenship – the Tax Administration states that the number does not change regardless of changes to the data on the basis of which it was assigned.
Two OIBs. The Tax Administration says such situations are extremely rare, but can happen to Croatian citizens who have lived abroad for a long time: if they have changed their first name or surname in the meantime, apply with a foreign passport and do not state their Croatian citizenship, they may be given a second number. So always state in the application that you are a Croatian citizen. If it happens anyway, the first number assigned is the valid one, and the Tax Administration cancels the later one by a decision (Article 11 of the Act).

Sources

Note: this text is for information only and is not legal or tax advice; this site is not the official website of any public authority. Regulations and fees change — check with the competent authority before you apply.