Created by Commonwealth Act No. 186 and Republic Act No. 8291 (GSIS Act of 1997), GSIS is a social insurance institution that provides a defined benefit scheme under the law. It insures its members against the occurrence of certain contingencies in exchange for their monthly premium contributions.

GSIS members are entitled to an array of social security benefits, such as life insurance benefits, separation or retirement benefits, and disability benefits.

GSIS is also the administrator of the General Insurance Fund by virtue of RA 656 (Property Insurance Law). It provides insurance coverage to government assets and properties that have government insurable interests.

The GSIS covers all government workers except:

• Members of the Judiciary and Constitutional Commissions who are covered by separate retirement laws;
• Contractual employees who have no employee-employer relationship with their agencies;
• Uniformed members of the Armed Forces of the Philippines and the Philippine National Police, including the Bureau of Jail Management and Penology and the Bureau of Fire Protection.

Does not include: Barangay and Sanggunian officials who are not receiving fixed monthly compensation

Does not include: Employees who do not have monthly regular hours of work and are not receiving fixed monthly compensation (RIRR)