What Form N-400 Is
Form N-400 is the naturalization application. It moves a lawful permanent resident to full U.S. citizenship — with the right to vote, hold a U.S. passport, sponsor a broader range of family members, and never fear deportation for lawful conduct.
Naturalization is not automatic. USCIS reviews residence, physical presence, good moral character during the statutory period, English + U.S. civics knowledge, and attachment to the Constitution before granting citizenship. The process culminates in a naturalization interview and an oath ceremony.
N-400 Eligibility Requirements
Most applicants must meet all of the following. Exceptions exist for military service members and certain spouses of U.S. citizens deployed abroad.
5-Year (or 3-Year) Permanent Residence
Five years as a green-card holder — reduced to three years if married to and living with the same U.S. citizen spouse throughout that period.
Continuous Residence
No single trip abroad of six months or more. Trips between six and twelve months may still qualify with proof of continuous ties.
Physical Presence
Physically inside the U.S. for at least half of the statutory period — 30 months of the last 5 years, or 18 months of the last 3 years for citizen-spouse applicants.
Good Moral Character
No disqualifying criminal or immigration violations during the statutory period. Failure to file taxes, unpaid child support, or Selective Service violations can bar naturalization.
English + Civics
Ability to read, write, and speak basic English, plus a passing score on the USCIS civics test. Age-based exceptions apply (50/20, 55/15, 65/20 rules).
Attachment to the Constitution
Willingness to swear allegiance to the United States and to defend the Constitution and laws of the country.
Filing Fee
The USCIS filing fee for Form N-400 is $760 as of the April 2024 fee schedule. Applicants 75 or older pay a reduced fee. Military applicants and certain low-income applicants may qualify for a fee waiver (Form I-912) or reduced fee.
How to Apply for Naturalization with N-400
The naturalization process typically runs 6–12 months from filing to oath ceremony.
Confirm Eligibility
Review residence, physical presence, moral character, and English/civics readiness before filing. A mid-case ineligibility finding is the most common reason N-400 gets denied.
Prepare and File Form N-400
Complete the form and submit with the filing fee, two passport photos (if applying from abroad), and supporting documents. Online filing is available.
Biometrics Appointment
USCIS schedules a biometrics appointment at an Application Support Center 4–8 weeks after filing to capture fingerprints for background checks.
Naturalization Interview
A USCIS officer reviews the application, tests English proficiency, and administers the civics test (10 questions from a bank of 100; must answer six correctly).
Oath of Allegiance and Certificate
Approved applicants attend an oath ceremony — sometimes the same day as the interview — where they swear allegiance and receive their Certificate of Naturalization.
Documents Filed with N-400
Most applications include the following. The full checklist varies by residency history and personal circumstances.
Identity and Status
- Copy of both sides of your green card (Form I-551)
- Passport pages showing all trips outside the U.S. in the statutory period
- State-issued ID or driver's license
- Two passport-style photos (if filing from abroad or by mail)
Family and Marital
- Marriage certificate (for 3-year rule applicants)
- Divorce or death records for any prior marriages
- U.S. citizen spouse's birth certificate or naturalization certificate
- Children's birth certificates
Character and Compliance
- Federal tax returns for the statutory period
- Selective Service registration proof (males who lived in the U.S. between 18 and 26)
- Court records for any arrests, charges, or convictions
- Proof of child-support payments if applicable
Frequently Asked Questions About N-400
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