Naturalization has a consistent structure regardless of which path got you eligible: file, get fingerprinted, interview, test, and take an oath — though the eligibility requirements to reach that starting line vary by circumstance. * The most common eligibility path is having held a green card for 5 years as a lawful permanent resident, though that shortens to 3 years if you've been married to and living with a U.S. citizen the whole time. Active duty and veteran military service members have their own separate, often faster eligibility path, and children of U.S. citizens may qualify automatically under different rules entirely. You also generally need to have lived in the state where you're applying for at least 3 months, be at least 18, and demonstrate good moral character. * The application itself is Form N-400, filed online through a USCIS account. After filing, most applicants attend a biometrics appointment for fingerprints, then wait for USCIS to schedule the naturalization interview. * The interview combines two things at once: an officer reviews your application and asks questions about it, and you take the civics and English tests in the same appointment. The civics test covers U.S. history and government; the English test evaluates reading, writing, and speaking. Applicants who meet specific age and long-term residency thresholds, or who have a qualifying disability, may be exempted from one or both tests. * Once approved, the process concludes with the Oath of Allegiance — the formal ceremony where you officially become a U.S. citizen. The current filing fee is $760, though military applicants are exempt from paying it entirely.