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Procedures and Formalities

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Obtaining the Social Security / Affiliation Number

Procedure for obtaining a Social Security / Affiliation number



The Social Security Number identifies citizens in their relations with the Social Security system.

What is the Social Security system

  • All citizens.
  • Employers, for all workers who are hired to work for them and do not have a social security number.
  • The Provincial Directorates or Administrative Offices of the Social Security Treasury General will assign it when workers or employers fail to meet their obligation.

Form TA1

  • National Identity Document
  • Residency Card or Passport.
Where to process it:

At the Administrative Office of the Social Security Treasury General corresponding to the citizen's home address or place of work. If you have a digital certificateyou can access the Social Security number Assignment service at the e-Office.


It must be applied for prior to the registration and affiliation application or the application for any benefits or service.

Other important information:

The Social Security Number becomes an Affiliation Number at the time when the citizen begins a labour activity determining inclusion within the Social Security System.

Characteristics of Affiliation:

  • It is compulsory for all persons included within the System for purposes of rights and obligations.
  • It is a single procedure, valid for all the Schemes within the system.
  • It covers the entire life of the person included in the System.
  • It is exclusive.

Frequently asked questions


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