Form N-400, step by step

Your eligibility clock starts on the “Resident Since” date on your green card. On the 5-year route you can file up to 90 days before reaching 5 years; on the 3-year marriage route, up to 90 days before reaching 3 years. Use the USCIS Early Filing Calculator: USCIS rejects applications filed even one day too early.

Add up your trips abroad. You need at least 30 months physically in the U.S. in the last 5 years (18 months in the last 3 years on the marriage route). Any single trip over 6 months needs a closer look, and a trip of 1 year or more generally breaks continuous residence.

• Check that you have lived at least 3 months in the state or USCIS district where you will file.
• If you are on probation or parole, USCIS will not approve the application until it ends.

Most of the N-400 is history. Write it down before you open the form:

• Every address where you lived for the past 5 years (or 3 years), with dates.
• Every employer or school for the same period, including gaps and self-employment.
• Every trip outside the U.S. of more than 24 hours during the statutory period, with departure and return dates. Your passport stamps and airline records help.
• Marriages and divorces for you and your spouse, and information about all your children.
• Any arrest, citation, detention or charge anywhere in the world, even if dismissed, expunged or from when you were a minor.

Answer every question. The officer will go over your answers under oath, so they must match your documents and what you say at the interview.

Part 9 is the long list of “Have you ever…” yes/no questions: claiming to be a U.S. citizen, registering to vote or voting, taxes, organizations, crimes, immigration violations, and your attachment to the Constitution. Read each question slowly. If an honest answer is “yes,” answer “yes” and explain; a hidden problem is usually far worse than a disclosed one. The N-400 instructions say to report all offenses, including expunged or pardoned ones and those committed before age 18.

If anything in your history is complicated (arrests, long trips, past immigration problems, unpaid taxes, a past vote), consider talking to an accredited representative or immigration attorney before filing. This site is information, not legal advice.

• Online: $710, filed through a USCIS online account. You can upload evidence and see notices online.
• Paper: $760, mailed to the address in the instructions.
• Reduced fee: $380 with proof of household income, paper filing only.
• Fee waiver: no fee, with Form I-912 or a written request, paper filing only.
• Members and veterans of the U.S. armed forces filing under the military provisions generally do not pay.

DHS proposed in June 2026 to raise the N-400 fee and end the reduced fee and fee waivers. As of October 2026 that was a proposal, not the current fee. Always check uscis.gov/n-400 and the fee calculator on the day you file.

You get a receipt notice (Form I-797C) with your receipt number. Then come the biometrics appointment (if required) and the interview notice.

• Keep a copy of everything you submitted and bring it to the interview.
• If you move, update your address with USCIS within 10 days; missed notices are a common cause of delays.
• Avoid long trips abroad while your case is pending; you must still be eligible on interview day and at the oath.
• In August 2026 USCIS reintroduced neighborhood investigations under INA 335(a), so USCIS may check your residence, employment or references.