What is Form N-400?

Form N-400 Explained: Your Guide to the Application for U.S. Citizenship

If you're a Lawful Permanent Resident (green card holder) and feel ready to become a fully fledged U.S. citizen, you’ll need to submit Form N-400, Application for Naturalization. This is the official application you will file with USCIS to request U.S. citizenship.

The N-400 is a long and very detailed form that asks for basically a complete biographical history. Knowing what to expect can make the process much less intimidating. This guide will break down the different parts of the application and give you tips for filling it out.

What is Form N-400?

Form N-400 is the application used by a green card holder to apply for U.S. citizenship through the naturalization process. It's how you formally show USCIS that you meet all the eligibility requirements, such as having held your green card for the required amount of time and demonstrating good moral character.

You can find the official form and its instructions on the USCIS N-400 page. For most people, filing the N-400 online through a myUSCIS account is the easiest and most recommended method.

A Quick Checklist of Documents to Gather

The N-400 asks for a lot of specific dates and information. It’s a good idea to gather these documents before you start filling out the application so you have everything you need in one place.

Common Documents to Have Ready:

Breaking Down the N-400

The N-400 application is broken up into 18 different parts. Here’s a simple look at what some of the key sections will ask you for.

• Part 1: Information About Your Eligibility
  
  • Here, you'll check a box indicating why you are eligible (e.g., you've been a green card holder for 5 years, or for 3 years as the spouse of a U.S. citizen).
• Part 2: Information About You
  
  • This is your basic personal information: your full legal name, any other names you've used, date of birth, country of birth, and your A-Number.
• Part 5: Information About Your Residence
  
  • You must list every address where you have lived during the last five years, with no gaps in time.
• Part 7: Information About Your Employment and Schools
  
  • You must list every employer and school you have attended during the last five years.
• Part 9: Time Outside the United States
  
  • This is a very important section. You must list every single trip you have taken outside the U.S. in the last five years, including short trips to Canada or Mexico. You'll need the exact dates you left and the date you returned for each trip.
• Part 10: Information About Your Marital History
  
  • You'll provide details about your current spouse and any prior spouses, as well as your current spouse's prior spouses. You'll need dates of marriage, dates of divorce or death, and other biographical information.
• Part 12: Additional Information About You (The "Good Moral Character" Section)
  
  • This is the longest and most complex part of the form. It contains a long series of "yes" or "no" questions about your background.
  • Topics include:
    
    • Your tax filing history.
    • Any involvement with extremist groups or persecution.
    • Your entire criminal history, including minor traffic tickets and any arrests, even if the charges were dropped.
  • It is absolutely crucial to answer every question in this section truthfully. Answering "yes" to some questions may not automatically disqualify you, but hiding information can lead to a denial for lacking "good moral character." If you have any concerns about how to answer these questions, this is a key area where consulting with an immigration attorney is highly recommended.

Tips for Filling Out Form N-400

What Happens After You File the N-400?

After you submit your N-400 application, the journey isn't over. Here’s what comes next:

1. Receipt Notice: USCIS will send you a notice confirming they have your application.
2. Biometrics Appointment: You'll attend an appointment to have your fingerprints and photo taken.
3. Interview and Test: You'll attend the naturalization interview where a USCIS officer will review your application and test you on your English and U.S. civics knowledge.
4. Decision: USCIS will issue a decision on your application.
5. Oath of Allegiance: If approved, you will attend a ceremony to take the Oath of Allegiance and officially become a U.S. citizen.