Searching the Index

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.

Submit an Index Search

Why Do I Need an Index Search?

Index search results determine two things:

  1. If any record/s exists for the immigrant identified; and
  2. If records exist for the immigrant, including:
  • How many records,
  • What kind(s) of records,
  • Where those records are currently located, and
  • How to request the records.

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:

  • CIS has only one file for the immigrant; and
  • You can provide the only accurate file number to identify that file.

Why Can’t I Search the Index Myself?

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.

Whose Records and Files Are Indexed?

If a person is in our index this means that the agency:

  • Created and maintained a record or file at Agency Headquarters in Washington, DC, between 1893 and 1975.

    • This does not include ship passenger lists or border arrival manifests, all of which were created and maintained in our field offices (ports of entry).

  • Maintained a file in any agency office between 1955 and 1975.

    • This includes Chinese Exclusion Act case files now at the National Archives.

Another way to describe the persons in our index are those who:

  • Had a Board of Special Inquiry decision appealed to Washington between 1893 and 1944 (not everyone held for Special Inquiry);

  • Were the subject of a warrant for deportation between 1903 and 1950;

  • Were naturalized in any court (federal, state, territorial, or local) between September 27, 1906 and 1975;

  • Were admitted as an immigrant between July 1, 1924 and 1975;

  • Were granted Registry (later called Lawful Entry) between March 2, 1929 and 1975;

  • Were issued a Certificate of Derivative Citizenship or Repatriation between 1929 and 1975;

  • Registered as an alien between 1940 or between 1940 and 1975; or

  • Are unique individual cases.

How Do We Search?

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 why there 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.

What Should I Expect?

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.

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