Published on 7 March 2025
FAQ OASI number for individuals
You will find answers to the most frequently asked questions about the OASI number below:
The OASI number is a Swiss social security number and personal identification number. It is made up of 13 numbers:
This number is randomly generated and is completely anonymous. It is also “silent”, that is to say that there is no link between the number and the personal details of the individual to which it is assigned (surnames, given names, date of birth, etc.). Generally, it is allocated once, as early as possible in the administrative life of a resident on Swiss territory, or a person connected with one of the Swiss first pillar social security systems. The number remains valid for life, even if the individual’s demographic data changes (for example family name, nationality, etc.)
Generally, not knowing an OASI number should not prevent any administrative procedure, as it is not the responsibility of the citizen to provide an OASI number to establishments. All the establishments operating with an OASI number are able to refer to a register to find this information. An important exception is the creation of an electronic patient record. In this case, the citizen must provide their OASI number to healthcare services.
It may be useful to know that:
- Since 1 February 2010, the OASI number is printed on all Swiss health insurance cards.
- For all requests for family support, unemployment support or health insurance registration, providing an OASI number is not necessary. These establishments have access to this information or may request allocation of a number.
- For non-residents, it is not necessary to prove an OASI number for enrolment to schools, universities, or training centres. These establishments have the means to locate the number or ask for its creation.
Generally, an OASI number is allocated from the moment you have contact with Swiss administration.
The moment will depend on your individual situation:
• During 2008, an “initial allocation of an OASI number” operation allowed the entire population to be allocated an OASI number, including Swiss abroad.
• Since 2008 for all individuals born in Switzerland, an OASI number is automatically created at the time of inscription into the birth register.
• For foreign nationals, when settling in Switzerland, an OASI number is created by migration services.
• For individuals wishing to register for compulsory health insurance in Switzerland, the OASI number is created as needed by the health insurer.
• For Swiss citizens living abroad and their family members, an OASI number is allocated for each new consular registration with a local Swiss representative.
• For individuals wishing to work in Switzerland, the employer contacts the relevant compensation office. The latter sends a request for creation of an OASI number after the start of the employment contract.
• For foreign diplomats or foreign representation members as well as their families and employees, an OASI number is created when a legitimation card is issued by the Swiss representative.
If you have health insurance in Switzerland, you will find the OASI number on your health insurance card. The OASI number is also on your OASI insurance certificate which may be issued from the moment you are insured with OASI. (Request for insurance certificate (admin.ch))
If you do not have one, you may contact the residents’ registration office of your commune of residence.
Foreign diplomats, foreign representation members and organisations established in Switzerland as well as their families and their employees may contact the Permanent Mission of Switzerland to the UN, Service of Registration of the International Community. Swiss citizens living abroad and their family members may contact their local Swiss representative.
Foreign nationals who have paid contributions in Switzerland and who live abroad may contact the Central Compensation Office.
Holders of a Permit S may contact one of the federal asylum centres or Cantonal contact points.
You may contact upi@zas.admin.ch
It is no longer mandatory to have an OASI card and it is no longer automatically issued. If you wish to replace your insurance certificate.
Submit your request on the eCdC eService.To obtain a correction you must report the error to an OASI Compensation Office. For an overall view of compensation offices to which you have paid contributions, click the following link: InfoRegistre
The OASI number is anonymous and therefore does not provide any personal information. Identity theft is not possible with knowledge of an OASI number, even if it accompanied by other personal details such as surname, given name and date of birth.
This number does not allow access to information systems or other databases to which access is usually denied.
The sole function of the OASI number is to associate a given person with personal data within a collection of data. It is used exclusively for administrative purposes to identify an individual.
Further information is available in the Message concerning the modification of the federal law on old-age and survivor’s insurance (systematic use of the OASI number by authorities), particularly chapter 1.1.3.
No. As a general rule, the OASI number initially assigned to you should not change. For legal (protection of privacy) or administrative reasons, however, it may be necessary to change the number. Even if such a change is rare, it is not exceptional. In this case, the organisations which use the OASI number have the responsibility to update their files with the new OASI number (in accordance with Art. 153f, let. c OASIA). Files must be updated by these organisations and not by individuals.