Searching the Index Frequently Asked Questions

Why Do I Need an Index Search?

Since 1893, federal immigration and naturalization agencies have 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:

  • USCIS 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?

Access to USCIS records and indices are restricted for purposes of both law enforcement and privacy. 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 that protects us all.

Whose Records And Files Are Indexed?

Persons in our index are those for whom 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;

  • 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 and 1975;

  • And more.

How Do We Search?

Our goal is to find any and all information helpful to genealogical researchers. Even in cases where no match is found, we may try to explain why there is no record or try to find a record for another family member named in the request.

USCIS Genealogy index searchers always begin by reviewing each request for completeness and to identify clues to possible records. They then search the automated index by name, narrowing search results by date of birth, place of residence, country of birth, or other factors. Because different data fields are available for different file types, searchers modify their search several times to identify possible records.

Once one or more files are identified, searchers then work to determine if the file still exists, and if so, where. For example, some C-Files are split between a portion on microfilm and another portion in paper form. Cards representing paper C-files are searched to identify all C-File parts. Other file numbers may be searched again in a separate database or hard copy volumes to determine the file’s current location. If the Genealogy Program identifies a file available from the program in our search results, but later cannot find the file, a refund is due. For this reason we exhaust all efforts to ensure the file exists and can be found.

What Should I Expect?

USCIS Genealogy Index Search Requests are fulfilled in the form of a letter reporting the search results. All file references found in the index are identified with 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 survive. 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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