What is naturalization?

Naturalization is the legal process by which a foreign-born person becomes a U.S. citizen after meeting the eligibility requirements set out in the Immigration and Nationality Act of 1952 and administered by U.S. Citizenship and Immigration Services. Most applicants must be lawful permanent residents at least eighteen years old, have held green card status for five years, or three years if married to a U.S. citizen, demonstrate continuous residence and physical presence in the United States, show good moral character for the relevant statutory period, possess basic English literacy and oral skills, demonstrate knowledge of U.S. history and civics, and take the Oath of Allegiance.

Specific exceptions modify these rules. Applicants over fifty who have been permanent residents for twenty years, or those over fifty-five who have been permanent residents for fifteen years, may take the civics test in their native language. Applicants over sixty-five who have been permanent residents for twenty years take a simplified twenty-question civics test. Members and veterans of the U.S. armed forces may naturalize on accelerated timelines under sections 328 and 329 of the Immigration and Nationality Act. Children under eighteen may acquire citizenship automatically through a U.S. citizen parent under the Child Citizenship Act of 2000.

The application process begins with Form N-400, the Application for Naturalization, which currently costs seven hundred and ten dollars including biometric services as of fiscal year 2025. After filing, USCIS schedules a biometric appointment to take fingerprints, a photograph, and a signature. The agency then conducts background checks and schedules a naturalization interview, which typically occurs eight to twelve months after filing depending on the field office.

At the interview a USCIS officer reviews the application, asks questions to verify continued eligibility, administers the English and civics tests, and either approves the application, continues it for additional information, or denies it. Approved applicants take the Oath of Allegiance at a public ceremony, often within a few weeks of the interview, where they receive a Certificate of Naturalization that is the official proof of citizenship. The Oath includes promises to support and defend the Constitution, to renounce prior allegiances, to bear arms or perform noncombatant or civilian service if required by law, and to bear true faith and allegiance to the United States.

Each year approximately seven hundred thousand to one million people naturalize. The process traces its constitutional foundation to Article I Section 8, which empowers Congress to establish a uniform Rule of Naturalization. Naturalization candidates should know the basic stages of the process they are completing.