If the social insurance has not been registered, the social insurance agency shall verify the social insurance premium it should pay. Employees-free individual industrial and commercial households who voluntarily participate in social insurance, part-time employees who do not participate in social insurance in the employing unit and other flexible employees shall apply to the social insurance agency for social insurance registration. The state establishes a national unified personal social security number. Personal social security number is a citizen's identity number.
Article 2 of People's Republic of China (PRC) Social Insurance Law
The state establishes social insurance systems such as basic old-age insurance, basic medical insurance, industrial injury insurance, unemployment insurance and maternity insurance, so as to guarantee citizens' right to receive material assistance from the state and society in accordance with the law when they are old, sick, injured, unemployed and have children.
Article 4
Employers and individuals in People's Republic of China (PRC) pay social insurance premiums according to law, and have the right to inquire about payment records and personal rights records, and require social insurance agencies to provide social insurance consultation and other related services. Individuals enjoy social insurance benefits according to law and have the right to supervise the payment of their own units.