Form N-400 is the application for U.S. citizenship through naturalization. Filed by lawful permanent residents who meet eligibility requirements for residency duration, physical presence, good moral character, and English/civics knowledge.
Filing fee: $760 ($380 reduced) · Processing time: 10-18 months · USCIS link: uscis.gov/n-400
Eligibility requirements
Standard 5-year rule
- 5+ years as a lawful permanent resident
- 30+ months physical presence in U.S. during those 5 years
- Continuous residence (no trips of 6+ months)
- Good moral character
- English ability (read, write, speak)
- U.S. civics knowledge
- Attachment to U.S. Constitution
- Willing to take Oath of Allegiance
- 18+ years old
- Resided in USCIS field office district for 3+ months
3-year rule (married to U.S. citizen)
Same as 5-year rule, but with these reductions:
- 3+ years as LPR
- 18+ months physical presence
- Married to and living with the same U.S. citizen for those 3 years
- Spouse has been a USC for 3+ years
Other special categories
- U.S. military members (1 year service in peacetime, no LPR requirement during wartime)
- Spouses of USCs working abroad for U.S. employer
- Children of USCs (different rules — see N-600)
Filing process
- Verify eligibility (90-day early filing window allows filing 90 days before 5/3-year mark)
- Complete Form N-400 (online or paper)
- Pay filing fee ($760 standard, $380 reduced for income 150-200% of poverty)
- Submit with supporting documents
- Receive receipt notice with A-number and case number
- Attend biometrics appointment (~2-4 weeks after filing)
- Wait for interview scheduling
- Attend interview (English/civics tests, application review)
- Receive decision
- If approved, attend naturalization oath ceremony
- Receive Certificate of Naturalization
The English and civics tests
English test components
- Speaking: Evaluated during the interview
- Reading: Read 1 of 3 sentences in English correctly
- Writing: Write 1 of 3 sentences in English correctly
Civics test
10 questions selected from a published list of 100. Must answer 6 correctly.
(Note: The civics test was modified in 2020, then reverted to the 2008 version in 2021. Current testing uses the 2008 version with 100-question list.)
Exemptions
- "50/20" rule: Age 50+ and 20+ years as LPR — civics in native language, no English test
- "55/15" rule: Age 55+ and 15+ years as LPR — civics in native language, no English test
- "65/20" rule: Age 65+ and 20+ years as LPR — simplified civics test (20 questions vs 100)
- Medical disability: Form N-648 from doctor
Good moral character — what trips applicants up
USCIS examines the past 5 years (3 for spouses of USCs) for good moral character issues:
- Criminal history: Arrests, charges, convictions, even if expunged
- Tax issues: Failure to file, owing back taxes, false returns
- Selective Service: Males 18-26 must register
- Marital infidelity: Especially in 3-year USC spouse cases
- Lying on prior immigration applications: Including past USCIS forms
- Failing to support dependents: Child support delinquency
- Voting illegally: As non-USC voting in federal elections
- False claims to U.S. citizenship: Permanent bar to naturalization
- Drug offenses: Even minor possession, even with expungement
Filing N-400 with unresolved criminal issues, tax problems, or moral character questions can result in not just denial but also placement in removal proceedings. Always consult an immigration attorney before filing if you have ANY concerns.
After approval — Oath ceremony
After interview approval, you're scheduled for the Oath of Allegiance ceremony. Some cases involve same-day oath at the interview; most are scheduled within weeks at a courthouse or USCIS facility.
At the ceremony:
- Surrender green card
- Take Oath of Allegiance to U.S.
- Receive Certificate of Naturalization
- Now a U.S. citizen!
Immediately after:
- Apply for U.S. passport (Form DS-11)
- Register to vote
- Update Social Security records
- Consider sponsoring family members (now possible as USC)