National SOC Month

Understanding the Social Security Number

  • Written by Ron Brown

mug brownIn this issue we are going to take a close look at one of the major tools a tracer uses in his hunt, the social security number (SSN). It is said that one of the ways the United States differs from many other countries is that we do not issue a national identifier number, but our social security number, supposedly unique to each of us, comes pretty close.

The use of the SSN has expanded significantly since its inception in 1936. It was originally created solely to keep track of the earnings history of workers for Social Security entitlement and benefit computation purposes. It has since come to be used as a nearly universal identifier. Currently the SSN is assigned at birth, and enables identification and tracking of individuals as well as locating assets and financial information.

In this article I will attempt to briefly explore the history and meaning of the SSN, as well as the Social Security Administration’s (SSA) master file, generally known as the Numerical Identification System or Numident. I will also attempt to trace the historical expansion of the uses of the SSN by professional tracers.

Today, use of the SSN has expanded substantially and may be the most commonly used numbering system in the United States. As of December 2008, the SSA had issued over 450 million original SSNs, and nearly every legal resident of the United States had one. The SSN’s very universality has led to its adoption throughout government and the private sector as a chief means of identifying and gathering information about an individual.

Creating the SSN scheme and assigning SSNs to U.S. workers was no easy task. Passage of the Social Security Act in August 1935 set in motion a huge effort to build the infrastructure needed to support a program affecting tens of millions of individuals. A numbering scheme was seen as the practical tracking device and thus, the employer identification number (EIN) and the SSN were created. The current SSN is composed of three parts:

• The first three digits are the area number

• The next two digits are the group number

• The final four digits are the serial number The three-digit area number is assigned by geographic region. One or more area numbers were allocated to each state based on the anticipated number of SSN issuances in the state. Prior to 1972, the numbers were issued to local offices for assignment to individuals; it was thought this would capture information about the worker’s residence. Until 1972 the area number represented the state in which the card was issued.

• Generally, area numbers were assigned in ascending order beginning in the northeast and then moving westward. For the most part, people on the east coast have the lowest area numbers and those on the west coast have the highest area numbers.

• 586 was divided among American Samoa, Guam, the Philippines, Americans employed abroad by American employers and, from 1975 to 1979, Indochinese refugees.

• 580 was assigned to Puerto Rico and the U.S. Virgin Islands; sequences 581 through 584 and 596 through 599 were also assigned to Puerto Rico.

• Sequence 577 through 579 was assigned to the District of Columbia. • Sequences 587 through 588 and 589 through 595 were assigned to Mississippi and Florida, respectively, for use after those states exhausted their initial area number allotments.

• Sequence 729 through 733 has been allocated to the Department of Homeland Security (DHS) for SSNs issued through the Enumeration at Entry (EaE) program, described below.

• No SSNs with an area number in the 800s or 900s, or with a 000 area number, have been assigned.

• No SSNs with an area number of 666 have been or will be assigned.

In a July 3, 2007, Federal Register notice, the SSA solicited public comment on a proposal to change the way SSNs are assigned (SSA 2007b). Under this proposal, the SSA would randomly assign SSNs from the remaining pool of available numbers, and the first three digits would no longer have any geographic significance. The SSA contends that doing so would ensure a reliable supply of SSNs for years to come, and would also reduce opportunities for identity theft and SSN fraud and misuse. By understanding the SSN concepts and intricacies the professional tracer can better use SSNs to their advantage.

In the next issue we will explore the details of the group and serial numbers. Until then, good luck and good hunting.

Ron Brown is a member of the National Association of Fraud Investigators and the author of “MANHUNT: The Book.” Contact him at This email address is being protected from spambots. You need JavaScript enabled to view it..