It doesn't have to be together. For new employees, after signing a labor contract with the company, the company can apply for social security insurance only by virtue of the labor contract, and then the company will establish a new personnel file for the employees, and put the labor contract, social security approval and other personnel data into the personnel file for filing. When an individual applies for social insurance, the materials to be submitted include the ID card of the insured individual and the labor contract signed with the unit. You can apply for insurance after filling out the relevant forms, which does not involve personal personnel files. Some enterprises don't pay social insurance premiums to employees on the grounds that employees' files are not in the unit, which damages their legitimate rights and interests. Labor contract is an important basis for the establishment of labor relations between workers and employers, while personnel files cannot be used as the basis for the existence of labor relations. As long as there is a de facto labor relationship between workers and employers, workers should enjoy social insurance.

You don't need to check the files when you apply for insurance, but it doesn't mean that the files are useless. When an employee reaches the legal retirement age, the unit needs to submit the employee's personal file when going through the retirement examination and approval formalities with the relevant social security department, which is used to review the employee's age and working years and calculate the length of service, which has a certain impact on the retirement salary. And in the process of handling social security, some personal situations that need to be verified also need to be verified through personal files.

Legal basis:

Article 58 of the Social Insurance Law of People's Republic of China (PRC), the employing unit shall handle social insurance registration for employees within 30 days from the date of employment. 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.