US Naturalization Records: Finding Your Immigrant Ancestors

US Naturalization Records: Finding Your Immigrant Ancestors

US naturalization records document a foreign-born ancestor’s path to citizenship, and they come in three parts: the Declaration of Intention (“first papers”), the Petition for Naturalization (“second papers”), and the Certificate of Naturalization. Before September 27, 1906, any court of record — county, state, or federal — could naturalize an immigrant, so the records are scattered and the forms vary wildly. After that date the Bureau of Immigration and Naturalization standardized everything, and a duplicate of each record went to Washington. The National Archives holds federal naturalizations, county clerks and state archives hold the pre-1906 local ones, and the USCIS Genealogy Program holds the federal copies filed from 1906 onward.

I’ll be honest: the first time I went looking for a naturalization record, I assumed it lived in one tidy place, the way a birth certificate does. It doesn’t. An immigrant could naturalize in any of roughly 5,000 courts. Once you understand why the records are so scattered, though, the hunt gets a lot easier. This guide walks through what the documents are, where they hide, and how to actually find the one with your ancestor’s name on it — with a heavy lean toward Michigan and the Upper Peninsula, where the mining boom pulled in tens of thousands of immigrants.

What are naturalization records?

Naturalization records are the paperwork a court generated when an immigrant became a US citizen. The process was voluntary, it usually took at least five years, and it produced a paper trail in three stages.

• Declaration of Intention (first papers). The immigrant renounced allegiance to their old country and stated an intent to become a citizen. Before 1906 this might list only a name, home country, and date. After 1906 the standard form (Form 2202) asked for birthplace, date and port of arrival, and a physical description.
• Petition for Naturalization (second papers). Filed after the residency period was met — five years for most of US history. The petition is the richer document: name, date and place of birth, occupation, arrival details, and the names of witnesses, who were often relatives or neighbors.
• Certificate of Naturalization. The proof of citizenship handed to the new citizen once the petition was granted. The court kept a stub; after September 1906 a duplicate went to the federal government.

One tip I wish someone had told me early: if a family still has the declaration but no petition or certificate, the ancestor probably never finished the process and was never actually naturalized. That single fact has redirected more than one of my research trips.

How did the naturalization process work?

Naturalization was a two-step legal process that ran a minimum of five years, though people stretched it out for decades. An immigrant could file a declaration of intention after arriving (some waited two years, some waited twenty). After meeting the residency requirement — set at five years since 1802 — they filed a petition and swore an Oath of Allegiance. If the court approved, a certificate issued.

The two steps didn’t have to happen in the same court, or even the same state. Somebody might declare intention in New York right off the boat, then move to Michigan’s Copper Country for mine work and petition years later in Houghton or Keweenaw County. That’s why you sometimes have to search records in two places for one person.

Two exceptions worth knowing. Before 1922, a married woman usually became a citizen automatically through her husband — no separate paperwork. And children under 21 typically derived citizenship from a naturalizing father. So don’t expect to find first papers for every adult in a household; derivative citizenship left many people with no file of their own.

Before and after 1906: the dividing line that changes everything

September 27, 1906 is the date every genealogist should tattoo on their brain. It’s the hinge the whole search swings on.

Before September 27, 1906, US nationality law let any court of record naturalize — municipal, county, probate, state, or federal. Each clerk designed his own forms and decided what to ask. The result is maddening inconsistency: one county’s declaration gives you a birthplace and arrival port, the neighboring county’s gives you a name and nothing else. Only the naturalizing court kept a copy; no duplicate went to Washington. Never assume the petition holds more than the declaration — pull both.

After September 27, 1906, the Basic Naturalization Act imposed standard triplicate forms nationwide and created the Bureau of Immigration and Naturalization. The court kept the original, the immigrant got a copy, and a duplicate went to the federal Naturalization Service, where it became a Certificate File (C-File). Courts kept naturalizing — some local courts did so as late as the 1980s — but now there was a central federal copy. That federal copy is the one you can order today from USCIS.

Where are naturalization records stored?

Here’s the map I keep in my head when I start a naturalization search. Where a record lives depends on the court, the date, and whether a federal duplicate exists.

A couple of things trip people up. The National Archives holds federal court naturalizations but generally not the state and local ones — those stayed with county clerks or went to state archives. And there’s no single nationwide index to pre-1906 naturalizations. You go court by court, county by county.

How do I find someone’s naturalization record?

Finding a naturalization record is a process of narrowing down which court, then which repository. This is the sequence I follow, and it rarely fails me.

1. Nail down where and roughly when they naturalized. Federal census records are the best starting point — the 1900, 1910, 1920, and 1930 censuses report citizenship status (“Al” for alien, “Pa” for first papers filed, “Na” for naturalized) and often the year of naturalization. Start with our guide to census records to pin the location.
2. Search the county first. Look for the petition (second papers) in the county or city where the immigrant finally settled, since that’s usually where the process wrapped up. Contact the county clerk or check the state archives.
3. Check the federal courts. If they naturalized in a US district or circuit court, the file is at the National Archives facility serving that state. Remember there’s no central index — you search by location.
4. Order the federal copy from USCIS. For any naturalization after September 26, 1906, submit a Genealogy Index Search Request (Form G-1041) to get file citations, then a Genealogy Records Request (Form G-1041A) for the actual C-File.
5. Try the big online indexes. FamilySearch, Ancestry.com, and state archive databases have digitized and indexed millions of naturalization records. Search every spelling — immigrants Americanized surnames constantly, so a Finnish Mäki might sit in the index as Maki or Mackey.

Naturalization records in Michigan and the Upper Peninsula

Michigan is one of the better states for this work. The Archives of Michigan in Lansing holds local government records from all 83 counties, and its digital collection is putting more than 2 million naturalization records from Michigan circuit courts — created between 1821 and 1985 — online, added county by county since fall 2025. You can search by county, name, allegiance, birthplace, immigration year, and birth date, though records made before 1906 generally won’t list birthplace or arrival year.

The Upper Peninsula is where naturalization records really earn their keep. The copper and iron mines were an interior Ellis Island. Cornish miners — the “Cousin Jacks” — came for the hard-rock skills they’d learned in Cornwall, and you’ll find whole indexes of Cornish declarations in places like Keweenaw County, one running 1862–1901. Finnish immigration was even heavier; the Quincy Mining Company recruited its first Finns to Hancock in 1864, and by 1880 Finns made up roughly one in five residents around Red Jacket (Calumet). By 1902, the peak emigration year from Finland, more than 23,000 Finns applied for passports in a single year, and a large share landed in the Copper Country.

That density is why county-level genealogy sites for the Upper Peninsula — including the one for Mackinac County in the eastern UP — matter. County clerk offices, the Michigan Tech Copper Country Historical Collections, and Family History Library microfilm all hold naturalization journals and indexes that the big commercial sites haven’t fully digitized. When I’ve traced UP mining families, the local index almost always beat the national database.

Are naturalization records public information?

Yes — most naturalization records are public. Pre-1906 court records held by county clerks, state archives, and the National Archives are open to researchers, and federal naturalizations over a certain age are freely searchable. USCIS makes records from the Genealogy Program available to anyone for a fee, with no requirement to prove you’re a descendant. The main restriction is on more recent A-Files, where privacy rules apply until enough time has passed or the subject is confirmed deceased.

If you’re a naturalized citizen looking for your own file, that’s a different door: you file a Freedom of Information Act request with USCIS for your A-File, rather than going through the Genealogy Program.

Frequently asked questions

How do I find someone’s naturalization record? Start with a federal census to learn where and roughly when they naturalized, then search the county clerk or state archives for local records and the National Archives for federal court records. For naturalizations after September 26, 1906, order the federal copy from the USCIS Genealogy Program using an index search request (Form G-1041) followed by a records request (Form G-1041A).

Are naturalization records public information? Most are. Court and National Archives naturalization records are open to researchers, and USCIS makes historical files available to anyone through its Genealogy Program for a fee. Recent Alien Files (A-Files) are restricted by privacy rules until enough time passes.

How much does it cost to get a naturalization record from USCIS? Under the current USCIS fee schedule, a Genealogy Index Search Request costs $30 filed online or $80 on paper, and a Genealogy Records Request costs the same — $30 online or $80 on paper. Check the USCIS Fee Schedule (Form G-1055) before filing, since fees can change.

Where are Michigan naturalization records kept? Michigan naturalization records are held by county clerk offices and the Archives of Michigan in Lansing, which is digitizing more than 2 million circuit court records from 1821 to 1985. For the Upper Peninsula, also check county-level genealogy pages and the Michigan Tech Copper Country Historical Collections.

---

For more on tracing immigrant families across US records, see our Michigan genealogy hub and the companion guide to census records.