Demystifying the Social Security Death Index

The Social Security Death Index (also known as the SSDI, Social Security Master Death List, or other similar names) is perhaps the most misunderstood index that is commonly used by genealogical researchers. Why is there so much confusion about the SSDI? I am not sure exactly why, but perhaps its name suggests that its contents are more inclusive than they actually are.

In today’s society, nearly every American has a Social Security number. In the 1930’s, when the Social Security program came into existence, that was not the case. Many people did not get Social Security numbers because the program was initially available to certain types of workers. As time went on, people from other geographic territories of the United States such as Puerto Rico and the U.S. Virgin Islands were given access to the program. In the 1950’s and 1960’s, the Social Security program really expanded and most Americans became eligible for participation in it. This gradual expansion of the social Security program may be one of the reasons why people are confused by the Social Security Death Index and why they are unable to locate their ancestors within the index.

Another potential reason for confusion is that people may not know that the SSDI is most useful for researching 20th century ancestors. It is estimated that 98% of the 50 million entries in the SSDI are for deaths that occurred after 1962. In addition to the fact that only deaths of people that had Social Security numbers are recorded in the index, only the deaths of those people with Social Security numbers whose deaths were reported to the Social Security Administration are included in the SSI – whew, that was a mouthful- and another reason why your ancestor’s death may not be recorded in the SSDI.

You may be wondering what, if anything, the SSDI is actually useful for. There are two ways in which SSDI data can help you in your quest for genealogical knowledge. First, it can serve as a way to validate other research that you have done, such as confirming a date of death or city of last residence. The SSDI can also serve as a stepping-stone to further research because if you are able to locate your ancestor in there and obtain his or her approximate date of death and Social Security number, you can then obtain birth and death certificates as well as search for obituaries.