N-400

Application for Naturalization

Agency
USCIS
Revision
Edition 01/20/25
Fillable fields
440
Pages
14
Official source
USCIS form page
Checked
October 14, 2026
Fill N-400 online
Page 1 of form N-400

Form N-400: Application for Naturalization

Form N-400 is the application to become a U.S. citizen through naturalization, for people who were born outside the United States and are not already citizens. Most applicants are lawful permanent residents who have held a Green Card for several years.

The form asks for your residence, marriages, children, jobs, schools, trips abroad, and a long list of background questions. USCIS uses it to decide whether you meet the requirements, then you attend a biometrics appointment, an interview with English and civics tests, and, if approved, an oath ceremony.

Because the answers go under oath, accuracy matters more than speed. The trip list, the address history and the background questions are the parts that most often need care.

The title area of Form N-400 (edition 01/20/25) with the form name, agency and OMB number

What's on Form N-400

Part 1: Information about your eligibility

The basis for your application, such as 5 years as a permanent resident or 3 years as the spouse of a citizen.

Part 2: Information about you

Name, A-Number, date of admission as a permanent resident, birth details, and a question about requesting a disability exception to the English and civics tests.

Part 3: Biographic information

Ethnicity, race, height, weight, eye and hair color.

Part 4: Information about your residence

Where you have lived, and your physical and mailing addresses.

Part 5: Marital history

Your current and prior marriages, and your spouse's details when applicable.

Part 6: Children

Information about your children.

Part 7: Employment and schools

Where you have worked or studied.

Part 8: Time outside the United States

Every trip abroad, used to check continuous residence and physical presence.

Part 9: Additional information about you

Questions on good moral character and other eligibility topics.

Parts 10 to 16: Fee, signature and oath

Part 10 is the fee reduction request, Part 11 your statement and signature, Part 12 an interpreter, Part 13 a preparer, Part 14 additional information, Part 15 signing at your interview, and Part 16 the Oath of Allegiance.

How to fill out Form N-400

  1. 1

    Check your timing first

    You can file up to 90 days before you complete the continuous residence period. USCIS has an Early Filing Calculator, and it rejects applications filed too early.

    The general provision box in Part 1 of Form N-400, the five year basis that sets the earliest filing date
  2. 2

    Choose your eligibility basis in Part 1

    Select the basis that matches your situation and be ready to prove it.

    Part 1 of Form N-400 with the general provision eligibility box checked
  3. 3

    Fill in Part 2 with your Green Card details

    Enter your A-Number and admission date as shown on your card. Answer the disability exception question truthfully. A Yes means Form N-648 must be sent.

    Part 2 of Form N-400 with a sample date of birth and the date became a permanent resident entered
  4. 4

    List addresses, jobs, schools and trips completely

    Include every trip required by the instructions. If you need more space, use Part 14 and add your name and A-Number to each extra sheet.

    The table of trips outside the United States in Part 8 of Form N-400, with columns for departure, return and countries
  5. 5

    Answer the background questions in Part 9 yourself

    Read each in full. If any answer is Yes, USCIS explains what records to attach, such as arrest reports, court dispositions and proof of completed sentences.

    The start of Part 9 of Form N-400 with the yes and no background questions to answer yourself
  6. 6

    Gather the checklist items

    A copy of both sides of your Green Card, marriage and divorce records, tax documents, and Selective Service information if it applies to you.

    Part 5 of Form N-400 asking for marital status and the number of marriages that the marriage and divorce records support
  7. 7

    Sign Part 11

    A stamped or typed name is not accepted. You can fill the form online free on this page and print it to sign, or file through a USCIS account.

    The applicant signature and date lines in Part 11 of Form N-400 with a sample signature entered

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Where to file, fees and what happens next

Online or by mail

Most applicants can file online. If you are asking for a reduced fee or fee waiver, you must file a paper form. Mailed forms go to the address on the USCIS direct filing addresses page.

Fee

The fee is on the USCIS Fee Schedule page, with a reduced-fee option and a fee waiver request on Form I-912. Check the amount on the day you file.

Biometrics and interview

Applicants must generally give biometrics unless USCIS waives it. You then take the English and civics tests at an interview, unless you qualify for an exception based on age and years as a permanent resident or a medical condition.

Test exceptions

Age 50 or older with 20 years as a permanent resident, or 55 or older with 15 years, means no English test and the civics test in your language. Age 65 or older with 20 years gets a simplified civics test.

Your Green Card while it is pending

USCIS says the receipt notice extends an expiring Green Card for 2 years from its Card Expires date. If you lose it, you generally still file Form I-90.

Common mistakes

Filing too early, leaving out trips, skipping records for any arrest, missing signatures, and forgetting that long trips can break continuous residence. Absences of a year or more generally do so, and Form N-470 may preserve residence in some cases.

Related forms

Who needs to fill out Form N-400?

  • Most applicants

    USCIS lists these general requirements: you are at least 18, have been a lawful permanent resident for at least 5 years with continuous residence, have lived in your state or USCIS district for at least 3 months, and were physically present in the United States for at least 30 months (913 days).

  • Applicants married to a U.S. citizen

    The residence period is 3 years if you applied based on marriage to a U.S. citizen under INA section 319(a), and you must have been married to that citizen for at least 3 years when you file.

  • Military and other special categories

    Current and former members of the U.S. armed forces, and spouses of members or of citizens working abroad for qualified employers, follow separate rules and evidence in the instructions.

  • Everyone must also show

    Good moral character, attachment to the principles of the U.S. Constitution, basic English and civics knowledge unless an exception applies, and willingness to take the Oath of Allegiance.

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Questions about Form N-400

How early can I file Form N-400?

Up to 90 days before you complete the required continuous residence period, as long as you meet every other requirement when you file.

Do I have to take the English test?

Most applicants do. Exceptions exist by age and time as a permanent resident, and for qualifying disabilities with Form N-648.

Can I file the N-400 online?

Yes, unless you are requesting a reduced fee or fee waiver.

What if I have an arrest on my record?

The instructions and checklist list the documents you must send, depending on whether charges were filed, there was a conviction, or the record was cleared.

Can a lawyer file for me?

You may be represented at no cost to the government. The representative submits Form G-28.