A 9-digit code on a social security card with letters.

The system automatically generates. The card number on the social security card is a 9-digit number automatically generated by the system when the cardholder applies for a social security card. The definition of social security card number is different in different places, and the numbering rules are also different. Some directly use the employee ID number as the social security card number, such as Dongguan, while others make up a separate number as the social security card number.