The Social Security Act was created in 1935 to provide retirement benefits for older Americans. In 1939 the Act expanded to include spouses and minor children of retired or deceased workers. It would later help workers who became disabled. When medicare became law in 1965 many people over age 65 applied for social security numbers to receive benefits.
When you work, you pay taxes into Social Security based on your earnings (up to a certain amount), and receive the benefits when you retire, if you become disabled, or if you are a survivor or dependent of a worker who died. Your Social Security Number (SSN) is used to link your earnings and benefits.
Puckett, Carolyn.The Story of the Social Security Number. Social Security Bulletin, Vol. 69, No. 2, 2009. ssa.gov
There are three main resources best for genealogy provided by the Social Security Administration:
”Social Security Death Index” or SSDI reports people that have had social security numbers, and whose deaths have been reported to the administration, beginning with deaths reported in 1962.
Search the SSDI on FamilySearch.org
Search the SSDI on GenealogyBank.com (registration required)
Search the SSDI on Ancestry.com (subscription may be required)
“Social Security Applications and Claims Index, 1936-2007” online database is available on Ancestry.com, and only shows extracts of records:
A copy or abstract of a deceased person’s SS-5 Original Social Security Application can be requested for a fee, with form SSA-711: Request for Deceased Individual’s Social Security Record (PDF link) through the Freedom of Information Act (FOIA). Choose photocopy, not computer extract, as there is less room for transcription errors. You do not need a certified copy for genealogical purposes. Providing the Social Security Number is not necessary, but you will need to provide as much other information as possible and pay a slightly higher fee if you do not have it.
Things this social security application you’re requesting can tell you:
Full name at birth, including maiden name
mailing address at time of application
age, date of birth, place of birth
parents full names
sex, race
employment information
More information about Social Security Numbers:
You will never see any Social Security Numbers starting with 000, 333, or 666.
The SSN is broken down into Area number, Group Number, and Serial Number. The Area number, or first three numbers, were assigned geographically until 2011 (when they began assigning them randomly). Before 1972 it was based on the state where the card was issued, and after 1972 it was based on the zip code of the mailing address on the application. For example, someone with the first three digits of a SSN of 001, 002, or 003 would have either applied for a social security card in the state of New Hampshire or had a NH mailing address on their application (prior to 2011).
The Group Number, or second two numbers, were assigned odd numbers 01 through 09, then even numbers 10 through 98, followed by even groups 02 through 08, then odd groups 11 through 99.
The Serial Number, or last four numbers, were assigned in sequence starting with 0001 except every fifth number was chosen from 2001 - 2999 or 7001 - 7999. Serial number 0000 is never used. Again, this was until 2011 when the change to randomization occurred.
Sources for above:
The SSN Numbering Scheme - ssa.gov/history/ssn/geocard.html