Each repository answers a different question.
USCIS
Immigration and citizenship files
Historical C-Files and certain A-Files, genealogy searches, records requests, and Certificates of Non-Existence for records in USCIS custody.
Explore Immigration and citizenship filesNational ArchivesFederal court and federal agency holdings
Declarations, petitions, and related federal court records where the relevant regional archive holds them.
Explore Federal court and federal agency holdingsState or local custodianNon-federal court records
County clerks, state archives, historical societies, and local repositories may hold records created outside federal courts.
Explore Non-federal court recordsOfficial sources for this guidance
- Naturalization records — U.S. National Archives
- Form G-1566 instructions — U.S. Citizenship and Immigration Services
Search in an evidence-preserving sequence.
- Use indexes and family records to identify the likely name, residence, date, and court.
- Request the record from every repository with plausible custody.
- Keep the search parameters and negative responses, not only successful records.
- Compare the petition, oath, certificate information, and next-generation birth date before drawing a citizenship conclusion.
Official sources for this guidance
- Naturalization records — U.S. National Archives
- Form G-1566 instructions — U.S. Citizenship and Immigration Services
No single negative result closes every repository.
This guide is general information, not legal advice. Access rules, forms, fees, and processing conditions can change; verify the current instructions with the issuing office before ordering.
Official sources for this guidance
- Naturalization records — U.S. National Archives
- Form G-1566 instructions — U.S. Citizenship and Immigration Services
Primary sources
Verify before filing
These official sources were used for the factual review. Open the live instructions before ordering a record or submitting an application.
- Naturalization recordsU.S. National Archives
- Form G-1566 instructionsU.S. Citizenship and Immigration Services