Social Security Death Index

The Social Security Death Index (SSDI) is a database of death records created from the 's Extract. Most persons who have died since 1963 and who had a (SSN) and whose death has been reported to the  Social Security Administration will be listed in the SSDI.

Unlike the Death Master File, the SSDI is available online for free from several websites. The SSDI is a popular tool for genealogists and biographers. The database contains valuable genealogical data: the deceased person's birth date, death date, SSN, State or Territory where the SSN was issued, and last place of residence. Once a deceased person is found in the database, the person's Application for Social Security Card (Form SS-5) can be ordered from the Social Security Administration. The SS-5 contains additional genealogical data such as birth place, father's name, and mother's full.

Given the growing problem of and the importance of the Social Security Number as a personal identifier in the United States, it might seem unusual that these identifiers are released publicly. The principle involved is that living persons have a right to privacy which includes the right not to have their Social Security Number revealed, but once a person dies they lose their right to privacy and therefore the Social Security Administration can reveal their number and report their dates and places of birth and death.

The death index is used to prevent fraud so that no one can steal the identity of a dead person, and take out a or a  in a dead person's name.

Instances of famous people not being found in the index (such as the eccentric ) often contribute to theories that the particular person is still alive.