History and Genealogy
The USCIS Genealogy Program uses indices unlike any immigration or naturalization index available to the public. Our unique Master Index system is a combination of index tools—partially automated and partially manual—that work together to identify and locate old agency files and records.
Why Do I Need an Index Search?
Index search results determine two things:
Since 1893, the federal immigration and naturalization agencies created and maintained a variety of records for immigrants. These agencies often converted an immigrant’s records from one kind to another; because of this you will need an index search unless you are certain that:
Federal law requires that USCIS restrict access to its records and indices for both law enforcement and privacy purposes. While described as “historical,” the oldest indices include information dated as recently as 1975. Open access to such personal information about living persons would constitute a clear violation of the Privacy Act.
If a person is in our index this means that the agency:
Another way to describe the persons in our index are those who:
The USCIS Genealogy's goal is to find any and all information helpful to genealogical researchers. Even in cases where no match is found, we try to explain whythere is no record or try to find a record for another family member named in the request.
Our Index Searchers always begin by reviewing each request. They do this to ensure completeness and to identify clues to possible records. The Index Searchers then search the automated index by name, and narrow search results by date of birth, place of residence, country of birth, or other biographical information. Index Searchers modify their search several times to identify all possible records because index entries for different file types contain different data fields.
Once one or more files are identified, searchers then work to determine if the file still exists and where it exists. For example, some C-Files are split between a portion on microfilm and another portion in paper form. The Genealogy Team searches cards representing paper C-files to identify all C-File parts. Other file numbers may be searched again in a separate database or in hard copy volumes to determine the file’s current location.
The Genealogy Program will exhaust all efforts to ensure the file exists and can be found. However, if the Index Searcher identifies a file available from the Genealogy Program in our search results, but later cannot find the file, a refund of the Records Request fee will be provided.
If you submit an Index Search Request the USCIS Genealogy Program will send you a letter reporting the search results. The letter will identify all file references found in the index and provide instructions and additional information necessary to request the file(s) from the USCIS Genealogy Program, the Freedom of Information Program, the National Archives, or a state or local courthouse.
The indices contain many references to files that no longer exist. When a file no longer exists the Index Search Request response letter will provide all information available from the index record and explain that the file is no longer available.
Last Reviewed/Updated: 12/30/2015