What Is Form N-400? Eligibility, Fees and the Parts of the Form

Form N-400 (Application for Naturalization) is the form a green card holder files with U.S. Citizenship and Immigration Services (USCIS) to become a U.S. citizen. Applicants usually need to have had a green card for at least 5 years (or 3 years if married to and living with a U.S. citizen) and meet the requirements for residence, good moral character, English and civics. According to the USCIS N-400 page (checked October 15, 2026), the fee is $710 online and $760 on paper, and you can ask for a reduced fee or a waiver.

This article explains who can file, the fees, the parts of the form and what happens after you file. The full journey from filing to the oath ceremony is in U.S. Citizenship Test 2026: Every Step from Form N-400 to the Oath Ceremony.

Who can file Form N-400?

According to USCIS, there are several ways to qualify. The two most common:

Green card holder for 5 years

According to I Am a Lawful Permanent Resident of 5 Years (updated March 16, 2026), you need to:

• Be at least 18 years old when you file.
• Have been a permanent resident (green card holder) for at least 5 years.
• Have continuous residence in the U.S. for at least 5 years immediately before filing.
• Have physical presence in the U.S. for at least 30 months of those 5 years.
• Have lived for at least 3 months in the state or USCIS district where you file.
• Show good moral character for the 5 years before filing (and until the oath).
• Read, write and speak basic English and know the basics of U.S. history and government.
• Be attached to the principles of the U.S. Constitution.

Married to a U.S. citizen (3 years)

According to I Am Married to a U.S. Citizen, you need a green card for at least 3 years, living in marital union with your U.S. citizen spouse during those 3 years, 3 years of continuous residence, at least 18 months of physical presence in those 3 years, 3 months in the state or district where you file, plus the moral character, English, civics and Constitution requirements.

There are other bases too, such as service in the U.S. military. The N-400 instructions list them under Part 1.

How is "continuous residence" different from "physical presence"?

• Physical presence is the total number of days you were actually inside the United States. Form N-400 asks about your trips outside the U.S. to work this out.
• Continuous residence means keeping the U.S. as your home without a break. Long trips abroad can affect it.

How these are counted in a particular case, especially after long periods outside the U.S., is a question for a licensed immigration attorney.

Can I file early?

According to the Form N-400 instructions (edition 01/20/25), applicants on the 5-year or 3-year basis can generally file up to 90 days before they meet the continuous residence requirement, as long as they meet every other requirement. USCIS has an Early Filing Calculator to work out the date.

How much is the Form N-400 filing fee?

According to uscis.gov/n-400 (checked October 15, 2026):

Case	Fee	How to file
Full fee, online	$710	Online
Full fee, paper	$760	Paper
Reduced fee	$380	Paper only
Fee waiver (Form I-912)	$0	Paper only

Who qualifies for a reduced fee or a fee waiver?

According to the USCIS Poverty Guidelines page (in effect from January 13, 2026, checked October 15, 2026), for the 48 contiguous states and D.C.:

Household size	Fee waiver (≤150% of poverty guidelines)	N-400 reduced fee (≤400% of poverty guidelines)
1	$23,940	$63,840
4	$49,500	$132,000

Alaska and Hawaii have separate tables on the same page.

• Reduced fee of $380: household income at or below 400% of the federal poverty guidelines, with supporting documents, requested in Part 10 of Form N-400.
• Fee waiver with Form I-912: under the Form I-912 instructions, based on one of three grounds: receiving a means-tested benefit (such as Medicaid or SNAP), household income at or below 150% of the poverty guidelines, or financial hardship. Form N-400 is on the list of forms eligible for a waiver on the I-912 page.

Fees can change. Check uscis.gov/n-400 and the G-1055 Fee Schedule on the day you file.

What are the parts of Form N-400?

The 01/20/25 edition of Form N-400 has 16 parts (per the table of contents in the instructions):

Part	Contents
1	Information about your eligibility (the basis you are filing under)
2	Personal information: name, date of birth, green card date, nationality, disability exception request (item 11)
3	Biographic information: ethnicity, race, height, weight, eye and hair color
4	Where you have lived in the last 5 (or 3) years
5	Marital status and prior marriages
6	Information about your children
7	Employment and schools in the last 5 years
8	Time outside the United States (trips)
9	Additional information: the Yes/No questions
10	Request for a reduced fee
11	Applicant's contact information, certification and signature
12	Interpreter (if any)
13	Preparer (if someone other than the applicant)
14	Additional information (extra space and explanations)
15	Signature at the interview
16	Oath of Allegiance

Part 9 is the part most people need to read most carefully. N-400 Yes/No Questions: What Each One Asks explains each group of questions.

A few points from the N-400 page and the instructions:

• USCIS rejects an application without a signature.
• Every page must be the same edition, with the edition date at the bottom.
• If you need more space, use Part 14.
• In Part 11 you certify, under penalty of perjury, that all the information is complete, true and correct.

Should I file Form N-400 online or on paper?

According to USCIS, you can file online through a USCIS account or on paper. Filing online costs $50 less. However, anyone requesting a reduced fee or a fee waiver must file on paper.

What happens after I file Form N-400?

1. Biometrics: according to uscis.gov/n-400, N-400 applicants generally must provide fingerprints unless exempt. USCIS mails an appointment notice if you need to visit an Application Support Center.
2. Interview and tests: the officer asks about your application and tests your English (speaking, reading and writing) and civics. Applicants who filed on or after October 20, 2025 take the 2025 test (up to 20 of 128 questions, 12 correct to pass). See The 128 Civics Questions (2025 Test) and How to Study Them.
3. Result (N-652): granted, continued or denied.
4. Oath ceremony: you become a U.S. citizen after you take the Oath of Allegiance.

Processing times depend on the office; see USCIS Processing Times.

Older applicants may be exempt from the English test. See The Citizenship Test for Applicants 65 and Older.

What should I gather before filling out the form?

Form N-400 asks about the last 5 (or 3) years in detail. Having this ready makes it faster and more accurate:

• Your green card (both sides) and A-Number.
• Your home addresses, with start and end dates, for 5 years.
• Your employers or schools, with dates, for 5 years.
• The departure and return dates of every trip outside the U.S. in 5 years.
• Current and prior marriages, and information about your children.
• If they apply: documents about overdue taxes, arrests or court cases (see the document checklist in the instructions).
• If you are asking for a reduced fee or a waiver: proof of income or of the benefit you receive.

While you wait for your interview, you can start practicing with N400 Ready, Manna One Solution's free app for practicing the civics questions, reading, writing, speaking and mock interviews in English and Vietnamese.

Need someone to prepare your Form N-400?

You can fill out Form N-400 yourself. If you would like someone to prepare the paperwork, Manna One Solution's immigration document preparation service works online with clients across the U.S., in English or Vietnamese. Manna One Solution is not a law firm and does not give legal advice; some states require non-attorney immigration document preparers to register with the state, so we confirm the state you live in before taking your case. Questions about whether you qualify should go to a licensed immigration attorney.

Sources

• USCIS — N-400, Application for Naturalization (updated June 16, 2026; checked October 15, 2026)
• USCIS — N-400 Instructions (edition 01/20/25) (checked October 15, 2026)
• USCIS — Poverty Guidelines (checked October 15, 2026)
• USCIS — I-912, Request for Fee Waiver and the Form I-912 instructions (checked October 15, 2026)
• USCIS — I Am a Lawful Permanent Resident of 5 Years (checked October 15, 2026)
• USCIS — I Am Married to a U.S. Citizen (checked October 15, 2026)
• USCIS — Processing Times (checked October 15, 2026)