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    A social security number (SSN) is a nine-digit number issued by the U.S. government s Social Security Administration to U.S. citizens, permanent residents, and other qualifying individuals. Created in 1936 to uniquely identify U.S. workers to determine the distribution of social security benefits under the new Social Security program, the use of social security numbers has since expanded as a leading way to gather information about a person, including tax records, and medical and employment history. It is also often necessary to get a job and receive social security benefits and other government services.

    How SSNs Are Generated

    Social security numbers have a three-part composition: AAA-GG-SSSS. The first three digits, the area number, were originally assigned by region. The next two digits, the group number, was initially used in 1936 as an administrative distribution tool. The final four numbers, the serial number, are a straight numerical series of numbers from 0001 9999 within each group.

    To help protect the integrity of the SSN and to preserve the longevity of the nine-digit system, the Social Security Administration, in 2011, changed the way SSNs were issued to randomization. The new approach eliminates the area number, eliminates the significance of the highest group number, and previously unassigned area numbers were introduced for assignment excluding area numbers 000, 666 and 900-999.

    Who Gets an SSN

    Since the inception of the social security number, social security cards have been used to provide a record of the number issued to an individual. Three types of cards are currently issued:

    1. The most common social security card is issued to U.S. citizens and permanent residents and features the cardholder s name and SSN.
    2. Individuals who are lawfully admitted to the United States temporarily under a DHS (Department of Homeland Security) Work authorization receive a card that shows their name, social security number, and a “VALID FOR WORK ONLY WITH DHS AUTHORIZATION” restriction.
    3. For individuals who are lawfully admitted to the United States without DHS work authorization but have a valid reason for an SSN, or need a number because of a federal law requiring a social security number to get a benefit or service receive a card that includes the NOT VALID FOR EMPLOYMENT restriction.

    Individuals meeting all of the requirements can apply for a social security number via the Social Security Administration using Form SS-5.

    SSN and Personal Data Privacy

    Social security numbers, in their widespread use as a primary form of identification and authentication, are personally identifiable information (PII), which makes them susceptible to data privacy and cybersecurity breaches, including phishing and hacking. Often housed on computer networks within government agencies and private organizations that continually face cyber attacks, SSNs are vulnerable to a wide spectrum of identity theft and medical, tax and banking fraud.

    As a result of the ongoing threat of large-scale data breaches, calls to eliminate the use of SSNs as identification and authentication have grown. National and local governments have implemented data privacy regulations that restrict what personally identifiable information can be collected and used, while organizations must be transparent about how they are using PII with the creation of privacy policy statements and agreements that allow individuals to opt-in or out.

    In 2018, the European Union established GDPR (General Data Protection Regulation), which outlines strict data protection guidelines and restrictions, while in the U.S., California s CCPA (California s Consumer Privacy Act), HIPAA (Health Insurance Portability and Accountability Act), and the Payment Card Industry Data Security Standard (PCI-DSS), offer data protections for PII use involving consumer data, medical records and credit card transactions.

    SSN Alternatives

    In addition to government-led restrictions on using SSNs, alternative forms of technology-backed ID have been proposed and implemented worldwide, including the use of encrypted electronic ID cards and the implementation of biometric identification such as fingerprints, voice control, iris and facial recognition scans for authentication at financial and government institutions.

    Fear around the irreplaceability of biometrics as well as the possibility of hackers or ID thieves mimicking voice IDs, has been tempered by the introduction of anti-spoofing technology that is advanced enough to know when someone is fraudulently pretending to be someone else.