Social Security number

A social security number (SSN) is a nine digit number resembling "123-00-1234" which is issued to an individual by the Social Security Administration of the United States federal government. It is commonly referred to as the SSN.

The British equivalent is a National Insurance number[?], generally called a NI Number.

The Canadian equivalent is a Social Insurance number[?], generally called a SIN Number.

Table of contents 1 Purpose and use 2 Structure 3 Valid SSNs 4 SSNs Invalidated by Use In Advertising 1 External Links

Purpose and use

The original purpose of this number was to administer the Social Security program. The SSN, however, has also come to be used as a "primary key" (a de facto national ID number) for identifying and tracking individuals within the United States. The U.S. Internal Revenue Service, for example, uses the SSN as the taxpayer identification number (TIN) for tax administration purposes. Each taxpayer and spouse is required to enter his/her own SSN on their federal tax return. Additionally, payroll and benefits, university student records, credit records[?], and driver's licenses are frequently indexed by Social Security number and hence disclosure and processing of these numbers is of major concern to privacy advocates.

Structure

The nine-digit Social Security number is divided into three parts.

1. The first three digits are the area number. If the Social Security number was assigned before 1973 (when Social Security cards were issued by local offices) the area number reflects the State where the Social Security number was applied for. Since 1973, social security numbers have been issued through a central office. The first three digits of a social security number are determined by the ZIP Code of the mailing address shown on the application for a social security number.
2. The middle two digits are the group number. They have no special geographic or data significance but merely serve to break the number into conveniently sized blocks for orderly issuance.
3. The last four digits are serial numbers. They represent a straight numerical sequence of digits from 0001-9999 within the group.

Valid SSNs

Any SSN conforming to one of the following criteria is an invalid number:

• Any field all zeroes (no field of zeroes is ever assigned).
• First three digits above 770

A pamphlet entitled "The Social Security Number" (Pub. No. 05-10633) provides an explanation of the SSN's structure and the method of assigning and validating Social Security numbers.

SSNs Invalidated by Use In Advertising

SSNs used in advertising have rendered those numbers invalid. One infamous instance is that of the E. H. Ferree Company[?] in Lockport, New York[?], which in 1938 decided to promote its product by showing how a Social Security card would fit into its wallets. Over time the number that appeared (078-05-1120 (http://www.ssa.gov/history/ssn/misused)) was claimed by over 40,000 people as their own.

Other numbers which have been widely used in advertising include:

 002-28-1852,  042-10-3580,  062-36-0749,  078-05-1120,  095-07-3645
 128-03-6045,  135-01-6629,  141-18-6941,  165-16-7999,  165-18-7999
 165-20-7999,  165-22-7999,  165-24-7999,  189-09-2294,  212-09-7694
 212-09-9999,  306-30-2348,  308-12-5070,  468-28-8779,  549-24-1889 

In order to prevent misuse, the Social Security Administration requests that Social Security cards shown in advertisements only use numbers guaranteed to be unused and invalid. These approved numbers are in the range 987-65-4320 through 987-65-4329.

External Links

• Social Security Administration (http://www.ssa.gov/)
• Frequently Asked Questions on SSNs and Privacy (http://cpsr.org/cpsr/privacy/ssn/)
• The Woolworth Card (http://www.snopes.com/business/taxes/woolssn.htm) - The SSN 078-05-1120 has been claimed by thousands of people since the late 1930s