To locate naturalization records, you must know the specific court and state in which your ancestor became naturalized and the approximate date. Not all naturalization records are held at the National Archives and Records Administration (NARA). NARA will only house the records if the naturalization occurred in a Federal court.
Prior to September 27, 1906, any "court of record" (municipal, county, state, or Federal) could grant United States citizenship. Often petitioners went to the court most geographically convenient for them. As a general rule, the National Archives does not have naturalization records created in state or local courts. However, a few indexes and records have been donated to the National Archives from counties, states, and local courts. Researchers should contact the National Archives facility serving the state in which the petitioner resided to determine if records from lower courts are available.
Beginning September 27, 1906, US naturalization law imposed a fee structure that encouraged the transfer of naturalization to Federal courts. It took time for the lower courts to let go of the practice, so researchers may need to look at lower courts if the National Archives does not maintain a record of naturalization from the early-mid 20th century.
If a naturalization took place in a Federal court, naturalization indexes, declarations of intention (with any accompanying certificates of arrival), and petitions for naturalization will usually be in the National Archives facility serving the state in which the Federal court is located. No central index exists.
To ensure a successful search with the National Archives researchers should include:
name of petitioner (including known variants);
date of birth;
approximate date of entry to the US;
approximate date of naturalization;
where the individual was residing at the time of naturalization (city/county/state);
and country of origin
In most cases, the National Archives will not have a copy of the certificate of citizenship. Two copies of the certificate were created – one given to the petitioner as proof of citizenship, and, after September 26, 1906, one forwarded to the Immigration and Naturalization Service (INS).
Certificates of citizenship were issued by the Federal courts until October 1991 when naturalization became an administrative function under the INS.
All INS records are now overseen by the US Citizenship and Immigration Services (USCIS). USCIS maintains duplicate copies of court records (including the certificate of citizenship) created September 27, 1906-March 31, 1956 within Certificate Files (C-Files). Beginning April 1, 1956, INS began filing all naturalization records in a subject’s Alien File (A-File). C-Files and certain A-Files can be requested through the USCIS Genealogy Program.
