How to Become a U.S. Citizen: The N-400 Naturalization Guide

Becoming a U.S. citizen through naturalization is the final step in many immigrants' journeys — it grants the right to vote, a U.S. passport, protection from deportation, and the ability to petition for more family members. The process runs on Form N-400, Application for Naturalization. This 2026 guide walks through eligibility, the step-by-step filing, fees, the interview and tests, and the oath ceremony. Figures come from USCIS; always confirm current fees on the official fee schedule before filing.

Are You Eligible to Naturalize?

The core requirements under the Immigration and Nationality Act are:

All applicants must also demonstrate good moral character (generally for the statutory period), an attachment to the U.S. Constitution, and the ability to read, write, and speak basic English plus pass a civics test — unless they qualify for an age-and-residence exemption or a medical-disability waiver (Form N-648).

The N-400 Process, Step by Step

1. Confirm eligibility and file Form N-400

You can file online or by mail, generally as early as 90 days before you meet your 5- or 3-year residence requirement. Answer every question honestly — the application asks about travel, taxes, dependents, and any criminal history.

2. Pay the fee (or request a waiver)

See the fee table below. Lower-income applicants may qualify for a reduced fee or a full fee waiver (Form I-912).

3. Attend biometrics

USCIS typically schedules a biometrics appointment to capture fingerprints and a photo for background checks. Some applicants have prior biometrics reused.

4. Interview, English test, and civics test

At the interview, a USCIS officer reviews your N-400 and administers the English (reading, writing, speaking) and civics tests. Study with our naturalization and citizenship test guide and rehearse the officer's questions using our 2026 citizenship interview questions.

5. Take the Oath of Allegiance

Once approved, you receive a notice for a naturalization oath ceremony. You become a citizen the moment you take the oath and receive your Certificate of Naturalization.

N-400 Fees and Timeline (2026)

How Long Does It Take?

Nationally, N-400 processing in 2026 typically runs about 8 to 14 months from filing to oath, but it varies widely by field office and case complexity. Compare your posted time and case status against the current figures in our USCIS processing times guide.

After You Naturalize

Your Certificate of Naturalization is proof of citizenship — use it to apply for a U.S. passport and to update your Social Security records. Keep it safe; if it is lost or damaged, you can request a replacement with Form N-565, explained in our N-565 replacement certificate guide.

Dual citizenship

The United States allows dual citizenship, so U.S. law does not require you to give up your original nationality. However, some countries automatically revoke citizenship upon foreign naturalization. Check your home country's rules before your oath ceremony so there are no surprises.

Continuous Residence and Physical Presence

Continuous residence means keeping your primary home in the U.S. for the required period; a single absence of more than six months can break it, and absences of a year or more almost always do. Physical presence is different — it counts the actual days you spent inside the U.S., which must total at least half of the required period (30 months on the 5-year path, 18 months on the 3-year path). Keep a travel log, because USCIS reviews your trips closely at the interview.

Good Moral Character

USCIS must find that you have shown good moral character (GMC), generally during the statutory period before filing and up to the oath. Issues such as unfiled taxes, unpaid child support, a DUI record, unlawful voting, or a false claim to U.S. citizenship can raise GMC concerns and require careful documentation. Some serious crimes are a permanent bar. If you have any arrest, citation, or tax problem, gather the records and consider consulting an immigration attorney before you file.

The English and Civics Tests

At the interview you must read one of three sentences correctly, write one of three correctly, and answer the officer's spoken questions to show basic English. The civics test is oral: the officer asks questions from the official list on U.S. history and government, and you must answer a passing number correctly. Applicants who are older with long residence, or who have a qualifying medical disability, may be exempt or use accommodations. Study the free USCIS materials alongside our citizenship test guide.

Special Paths: Military Service and Children

Some applicants naturalize under different rules. Members of the U.S. armed forces may qualify with reduced or waived residence requirements and file Form N-400 with Form N-426 to certify service. Children under 18 often acquire citizenship automatically when a parent naturalizes, under the Child Citizenship Act, and may document it with Form N-600 rather than filing their own N-400. If either situation applies, confirm the exact requirements with USCIS.

Common Reasons an N-400 Is Delayed or Denied

• Continuous-residence breaks from long trips abroad;
• Tax or child-support issues that raise good-moral-character questions;
• Undisclosed criminal history — even old or minor offenses must be listed with records;
• Incomplete evidence, which triggers a Request for Evidence and delay.

Answer every question truthfully; a misrepresentation is far more damaging than the underlying issue it hides.

Preparing for the Interview

Bring your green card, state ID or driver's license, and any documents USCIS lists in your appointment notice — updated tax transcripts, marriage or divorce records, and travel history if requested. Review your own N-400 answers beforehand so they match what you tell the officer. If you must reschedule, do so promptly through your USCIS online account to avoid administrative closure. Arriving prepared is the simplest way to keep your timeline on track.

Frequently Asked Questions

How much does it cost to file Form N-400 in 2026?

As of 2026, USCIS charges $710 to file Form N-400 online or $760 by paper, which includes biometrics. A reduced fee of $380 is available between 150% and 400% of the Federal Poverty Guidelines, and a full fee waiver using Form I-912 at or below 150%. Confirm current amounts on the USCIS fee schedule, as an increase has been proposed.

How long does the naturalization process take?

Most N-400 cases take roughly 8 to 14 months from filing to the oath ceremony in 2026, though times vary by field office. The process includes biometrics, an interview with the English and civics tests, and the oath. You can track your case in your USCIS online account.

Do I have to give up my current citizenship to naturalize?

U.S. law does not require you to renounce another nationality, and the United States permits dual citizenship. However, some countries do not, and may revoke your citizenship when you naturalize elsewhere. Check the rules of your country of origin before your oath ceremony so you understand the consequences.

Last reviewed: July 2026 · Reviewed by USImmigrationLaw.Today editorial team.