N-400
Citizenship (N-400)
Apply for U.S. naturalization.
This guide explains what the form is — not whether you should file it. Only a licensed attorney or BIA-accredited representative can advise you on eligibility.
Form N-400 is the application to become a U.S. citizen through naturalization.
This form is filed by individuals who wish to apply for U.S. naturalization. USCIS reviews each application and makes all eligibility determinations -- this guide does not.
Government filing fee
$760 online / $710 paper (includes biometrics)
Fees may change. Always verify the current fee at uscis.gov before filing.
Government fees are paid directly to USCIS, not to Reunite Assure. Verify current fees at uscis.gov before filing.
Typical processing time
Approximately 8-18 months (estimate only; times vary by field office and are not guaranteed).
Interview required: An interview is required for most N-400 applicants.
Processing times are estimates only and are not guaranteed.
Documents typically required
- Permanent resident card (green card)
- Passport-style photos
- Evidence of continuous residence (e.g., tax returns, lease agreements)
- Travel records showing any trips outside the U.S.
- Additional documents listed in the official USCIS instructions
This list is for general reference only. Review the official USCIS instructions for the complete and authoritative checklist.
Reunite Assure software fee
Self-Prep
$225
Complete
$375
Official USCIS page
uscis.gov/n-400