Is it illegal for companies to buy social security on their behalf?

Legal analysis: not illegal. If the employee has a labor relationship with the company, it needs to be paid with the company's social security account. Secondly, there is a remittance account. At present, many small and medium-sized companies may not have their own social security accounts, and it is illegal not to pay social security for employees, so they can only choose remittance service. Remittance service is an agreement signed between remittance companies and enterprises, which belongs to the nature of company-to-company, but the labor relations of employees are still signed with enterprises, and social security is also paid normally.

Legal basis: People's Republic of China (PRC) Social Insurance Law.

Article 57 An employing unit shall, within 30 days from the date of its establishment, apply to the local social insurance agency for social insurance registration with its business license, registration certificate or unit seal. The social insurance agency shall, within fifteen days from the date of receiving the application, examine and issue the social insurance registration certificate. Where the social insurance registration items of the employing unit are changed or the employing unit is terminated according to law, it shall, within 30 days from the date of change or termination, go to the social insurance agency to handle the change or cancellation of social insurance registration. The administrative department for industry and commerce, the civil affairs department and the organization management organ shall promptly notify the social insurance agency of the establishment and termination of the employing unit, and the public security organ shall promptly notify the social insurance agency of the birth, death, household registration, transfer and cancellation of an individual.

Article 58 An employing unit shall, within 30 days from the date of employment, apply to the social insurance agency for social insurance registration for its employees. 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.