The roots of the current form of social insurance in the Islamic Republic of Iran go back to 1930, the time of constructing the railway, and which was established under the title of Workers' Provident Fund.

Thereafter, the structure of social security services was organized in 1975 in the form of the Social Security Organization  (SSO).

Currently, the SSO as the largest social insurance body, medical network and pension fund in the region covers around 40 million persons, which is equal to 50% of total population of the country.

In fact, this large covered population is due to the efforts of extending social security coverage to different groups of informal sector workers, which were very difficult to identify.

Three major groups of recently recognized and covered persons are:

•    Construction workers.
   
•    Carpet-weavers and handcraft artisans.
   
•    Iranians living abroad.
   

Covering the above-mentioned  groups in the informal economy  contributed to an increased range of social insurance coverage, estimated to be 13.5 million persons, through the enforcement of administrative procedures and regulations by the SSO.