A Complete Guide To

Form N-400, Application for Naturalization

Form N-400 Explained

What is Form N-400 used for?

Permanent residents use Form N-400, Application for Naturalization, to apply for U.S. citizenship through the naturalization process. Naturalization refers to the process in which a person not born in the United States voluntarily becomes a U.S. citizen. For foreign-born persons, naturalization is the most common way to become a U.S. citizen.

Nearly a million people naturalize a year and now enjoy the benefits of U.S. citizenship. New citizens receive a Certificate of Naturalization and may also request a U.S. passport immediately after naturalizing.

Eligibility to Become a U.S. Citizen

What are the requirements on the Application for Naturalization?

You must meet certain requirements before you are eligible to apply for naturalization with Form N-400. Generally, you must be a permanent resident who is at least 18 years old and fall into one of the following three basic eligibility categories:

  • Have been a permanent resident for the past 5 years | Learn more
  • Currently married to and living with a U.S. citizen and have been married to and living with that same U.S. citizen for the past 3 years | Learn more
  • Currently serving in the U.S. armed forces (or will be filing your application within 6 months of an honorable discharge) and have served for at least 1 year | Learn more

If you are applying based on five years as a permanent resident or based on three years as a permanent resident married to a U.S. citizen, you may file the application up to 90 days before you meet the “continuous residence” requirement. You must meet all the other requirements at the time that you file your application with USCIS.

The vast majority of applicants fall into one of the categories above. However, there are additional eligibility categories. You can check your eligibility by using CitizenPath's service to prepare the N-400 application. You don't have to pay unless you want to finish the application. You can check your eligibility for free.

N-400 Online Filing

Can Form N-400 be filed online?

USCIS offers an online filing option for the Form N-400, Application for Naturalization.  But there are tradeoffs when you use USCIS online filing. You can submit your application quickly. However, this doesn’t necessarily mean you get quick processing or protections from mistakes. If you are interested a quick approval, focus on submitting a well-prepared application package. It’s the difference between saving a couple of days with online filing versus saving several weeks with smooth processing. What’s more, USCIS is not your advocate. They are not looking out for your best interests. If you include information that damages your application or your immigration future, USCIS isn’t going to correct you.

For people who want to make sure they are preparing the application correctly, CitizenPath offers an affordable service created by immigration attorneys. CitizenPath’s Naturalization Package makes the application easy and gives you alerts if there’s a problem. You’ll also receive detailed filing instructions so you know exactly which supporting documents to submit with your application. CitizenPath even provides a money-back guarantee that USCIS will approve your application.

You may always download a copy of the Form N-400 PDF from the USCIS website. Occasionally, USCIS publishes new editions of the N-400 application. Make sure you are using an edition which USCIS accepts. Although you may use black ink to fill in your Form N-400 by hand, it’s preferable to file a typed application. This helps prevent mistakes and may improve intake speed.

Form N-400 Instructions

How do I fill out N-400?

CitizenPath's easy-to-use website helps you prepare the application quickly and accurately. Our online service provides step-by-step N-400 instructions so that you can fill out the application in the same day. We even give you a money-back guarantee that USCIS will approve your application.

If you prefer to fill out the Form N-400 PDF, you can download instructions from USCIS or follow this summary of directions.

General Guidance

  • Type or print answers in black ink only. 
  • Enter “N/A” if an answer is not applicable and "NONE" if your answer is zero.
  • Foreign language documents must be accompanied by a full English certified translation.
  • Submit your application with the current USCIS filing fee. Use a personal check, money order, cashier’s check or use Form G-1450 to pay by credit card.
  • Submit photocopies for all supporting documents unless an original document is specifically required.

Part 1

  • For Information About Your Eligibility, indicate how you are eligible to become a U.S. citizen. If you're not sure, review the detailed eligibility requirements above or use CitizenPath's Naturalization Package to see if you're ready.

Parts 2 and 3

  • For Information About You, list your current legal name and any other versions of your name from your permanent resident card, maiden name or other documents. If you married in the U.S., the marriage certificate is generally a legal name change document. You can start using your married name. USCIS will use this name to issue the Certificate of Naturalization. You'll find the date you became a lawful permanent resident on the front of your green card; it's the "Resident Since" date. If you have a parent who naturalized before your 18th birthday, it's possible that you became a citizen as well. If this may apply to you, check out citizenship through parents.
  • For Social Security Update, indicate if you want USCIS to communicate your new citizenship status to the Social Security Administration. Most people should select "Yes" as this is a major convenience as compared going to the SSA office in person. y disability or impairments for which you would like USCIS to provide accommodations. USCIS will make accommodations for you at the time of your biometrics screening and any other appointments.
  • For Biographic Information, answer how you identify in terms of race and ethnicity. Indicate other details about your height, weight, eye color and hair color.

Parts 4, 5, and 6

  • For Information About Your Residence, provide a mailing address where you can safely receive mail. USCIS will mail you notices and appointment information at this address. Also provide physical address history (up to five years) based on your requirements.
  • For Information About Your Marital History, enter all information to the best of your ability. If the basis of your N-400 application includes marriage to a U.S. citizen, it is important to be thorough. In particular, supply dates when previous marriages ended.
  • For Information About Your Children, provide requested details about all of your children, regardless of age, status or location.

Parts 7 and 8

  • For Information About Your Employment and Schools, list each employer and school you've attended (over the past five years for the standard applicant). Also list any self-employment or military service. If the space is not adequate, attach a separate sheet as an addendum.
  • For Time Outside the United States, list each trip abroad during your statutory period (five years for most applicants). Visits to Canada, Mexico, and the Caribbean are "outside the U.S." If you cannot reasonably find the dates of trip, estimate the dates to the best of your ability. Use this as a worksheet to make sure that you meet the continuous residence and physical presence requirements. CitizenPath's online service to prepare Form N-400 will do this for you automatically. Remember, any trip six months or longer will likely disrupt your continuous residence requirement.

Part 9

  • For Additional Information About You, take your time to carefully answer each question correctly. Your answers to these questions can affect the good moral character requirement for naturalization. Use your best judgement to determine if your answers or involvement with a group or organization conflicts with this requirement. If you are unsure, talk to an attorney.

Part 10

  • For Request for a Fee Reduction, you can now request a reduced fee on Form N-400. To qualify for the reduced fee, your household income must be less than our equal to 400 percent of the Federal Poverty Guidelines, at the time of filing, based on your household size.

Parts 11, 12, and 13

  • For Applicant's Contact Information, Certification, and Signature, provide your phone number(s) and email address. USCIS generally communicates by email and postal mail, but providing a phone number is important as a back up. Sign your application with black ink. A surprising number of N-400 rejections are the result of applicants forgetting to sign or signing in the wrong place.
  • For Interpreter and Preparer, provide information if applicable. If you prepared your Form N-400, it’s only necessary to sign as the “applicant.” If another person translated or prepared the application for you, be sure Parts 12 and 13 are filled in and signed appropriately.

Parts 15 and 16

  • Leave these sections empty. Do not answer or sign in any of the spaces. USCIS will have you enter information and sign in these sections at the time of your N-400 interview and oath ceremony.

This is an abbreviated list of Form N-400 instructions. We highly recommend that you download USCIS instructions or use CitizenPath’s service to prepare the application. CitizenPath provides filing instructions customized to your situation. You’ll get detailed N-400 instructions that explain which supporting documents to submit, how to organize, and where to mail.

Filing Addresses for the Application

Where to send Form N-400?

USCIS accepts the N-400 application via e-file and mail. They do not want applicants to submit the form in-person at USCIS offices. Due the various eligibility categories, there are many different Form N-400 filing addresses. The address depends on various factors such as the basis of eligibility and U.S. state of residence. For the most up-to-date address, refer to the USCIS N-400 direct filing addresses.

Although USCIS receives your N-400 application at these locations, they will process the application somewhere else. If you have an interview, it will be at a USCIS field office near that home address you provide.

N-400 Application Processing Time

How long does it take?

USCIS is reporting processing times in excess of one year. The processing time for Form N-400 can vary from 8 to 12 months for the majority of CitizenPath applicants. During the process, most people will need to attend three separate appointments: a biometric appointment, naturalization interview, and the oath ceremony. The best way to ensure a smooth process and quick processing time is to prepare a strong application. Of course, you must meet the eligibility requirements. But presenting a neat and well-organized application package is also important.

For an in-depth look at what happens after filing Form N-400, visit our N-400 processing time line.

Reporting for processing times only includes forms that were successfully filed. If an individual does not correctly prepare a form or otherwise does not satisfy eligibility requirements, USCIS will reject or deny these requests. For the most recent year, USCIS reported the following national statistics:

USCIS Rejections in 2023

MODERATE RISK

89,043 Rejections
USCIS Denials in 2023

HIGH RISK

98,861 Denials

How CitizenPath Helps You

Is there an inexpensive way to file the N-400 application?

CitizenPath's affordable, online service makes it easy to prepare Form N-400, Application for Naturalization. Designed by immigration lawyers, the Naturalization Package helps you eliminate the common errors that create delays, rejections and even denials. That's because the service alerts you when your answer to a question may be a problem. You'll also get customized filing instructions based on your situation. It's a powerful, do-it-yourself tool that puts you in control. And we've got your back -- CitizenPath provides live customer support and provides a money-back guarantee that USCIS will approve your application. Get started >>

STEP
1
Check Eligibility
No signup required.

We're going to ask you a few questions to make sure you're eligible and preparing the correct form.

STEP
2
Prepare Form N-400
There’s no obligation to purchase.

Our software will guide you through the N-400 application using simple step-by-step instructions.

STEP
3
Download, Print and File
Pay only $199 + USCIS fees.

Once you're completely satisfied, you’ll be able to print your N-400 and customized filing instructions.

CitizenPath Naturalization Package to file Form N-400 (Application for Naturalization)
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