What does the social security number mean?
Verified 30 September 2022 - Directorate for Legal and Administrative Information (Prime Minister)
Registration in the National Directory of Identification of Natural Persons (RNIPP) shall be subject to the allocation of a Registration Number (NIR).
The NIR is also called the "social security number". It is composed of 13 digits and is completed by a control key composed of 2 digits.
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Social security number

The NIR, created from civil status, is composed as follows:
1er digit | Gender: |
Next 2 digits | Year of birth |
Next 2 digits | Month of birth |
Next 5 digits | Place of birth: |
Next 3 digits | Serial number to distinguish persons born at the same place in the same period |
If you are foreign born, the 2 digits of the department code are replaced by 99 and the common code by an Insee code of the country of birth.
If you were born in Algeria, Morocco or Tunisia before the independence of these countries, a specific code may be used instead of the code 99 and the INSEE code of the country concerned.
Example :
91, 92, 93 or 94 for Algeria, 95 for Morocco and 96 for Tunisia
FYI
Two digits constituting a “control key” complete the social security number. This control key makes it possible to verify that the social security number is well formed.
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