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.