Naturalization Application

Find N-400 instructions and application fees information to complete and submit your naturalization application Form N-400

Form N-400

Application for naturalization, also known as Form N-400, is a government form used by green card holders to apply for his or her U.S. citizenship. Once you are eligible to apply, you will have to complete this N-400 application to initiate the process to become a United States citizen.

Here, we will give you information about:

  1. Who should file Form N-400
  2. N-400 application filing instructions including the application fees
  3. Required documents
  4. Additional helpful information for naturalization applicants

1. Who should submit the form N-400 application

In general, an individual who is qualified for naturalization may file the Form N-400 application. The N-400 instructions page mentions you must be at least 18 years of age at the time of filing, must have green card and continuously and physically present in the United States for the Statutory Period, and must have Good Moral Character. (You may find more detailed information as to basic eligibility requirements for naturalization, under our article Naturalization Requirements).

However, if you acquired or derived U.S. citizenship through at least one U.S. citizen parent or are a child of a U.S. citizen and live abroad, then you cannot use this form N-400. If your biological or legal adoptive mother or father is a U.S. citizen by birth, or was naturalized before you reached your 18th birthday, you may already be a U.S. citizen.

If you are not sure whether you qualify to use Form N-400, ask Lawfully for more information and N-400 instructions.

2. Form N-400 instructions for filing

  • Application fees
  • Processing time of N-400 application
  • Filing the Form N-400 application online
  • Filing the Form N-400 application by mail
  • Filing early for naturalization

N-400 application fees

The Form N-400 application fee$640.00
The biometric service fee$85.00
Total application fee amount$725.00

You must send the $725.00 fee with your N-400 application. Pay the fee with a check or money order created by a U.S. bank payable to the UNITED STATES DEPARTMENT OF HOMELAND SECURITY. Do not use initials such as “USDHS” or “DHS”. Do not send Cash.

You may also pay the application fee using a credit card. There is no additional fee for paying with a credit card. However, you will have to use the G-1450, Authorization for Credit Card Transaction.

IMPORTANT 1: If you are applying for naturalization based on your own service in the Armed Forces of the United States, no application fee is not required.

IMPORTANT 2: If you are 75 years old or older, or if you are filing on the basis of your service in the Armed Forces of the United States, DO NOT send the biometric services fee for fingerprinting with your N-400 application.

Learn more about the application fees, waiver and how to pay the fees here.

Processing time of N-400 application

Although it may vary depending on each case and the amount of pending application at the time with the USCIS field office, the current processing time for naturalization is approximately 8 ~ 14 months or more.

Find out estimated processing time for each step of naturalization here.

Filing the Form N-400 application online

You can file your Form N-400 application online unless you are applying from abroad or are applying for a fee reduction or waiver, in which case you must use the paper Form N-400 application and file by mail.

To submit the N-400 application online, you must create an online account with USCIS ( and complete the Form N-400 application electronically. Having an online account will allow you to:

  1. Pay your application fee online;
  2. Check the status of your case;
  3. Receive notifications and case updates;
  4. View personalized case completion date estimates;
  5. Respond to requests for evidence; AND
  6. Manage your contact information, including updating your address

Filing the Form N-400 application by mail

If you are filing paper Form N-400 for naturalization, you will have to send the form N-400 and the application fee by mail. The USCIS N-400 instructions page address as to where the form and other documents to be mailed depends on the state in which you live and the delivery service you choose. (For example, USPS vs. FedEx, UPS, or DHL).

If you are applying based on being a current or former member of the military, a spouse of a current member of the military, or a close relative of a deceased member of the military then you will have to send your Form N-400 and other supporting documents to a special address.

USCIS N-400 instruction page provides a list of the addresses to which applicants must send their N-400 and the application fee. (

Filing early for naturalization

The 90-day Early-Filing Rule

You may file Form N-400 application, 90-calendar days before you complete your statutory wait period requirement if your eligibility for naturalization is based upon being a (1) permanent resident for at least 5 years; or (2) permanent resident for at least 3 years if you are married to a U.S. citizen.

According to the USCIS N-400 instructions page, to determine the 90-day early filing date, look for the date on your green card. Then Add 3 or 5 years from the date you find on the green card and then subtract 90 days therefrom.

Check here for detailed information about naturalization requirements.


Bob who has met all other qualifications and is now simply waiting for the permanent resident statutory period to run. He finds a date in his green card which states, July 4, 2015. Bob’s 5-year wait period will be met on July 4, 2020. Bob may file his N-400 application as early as April 5, 2020.

IMPORTANT: You cannot actually become a U.S. citizen until after you have waited the full 3 or 5 years wait period. Filing early simply just places you a head of the line in the process.

Find out estimated processing time for the naturalization process here.

3. Required documents

In addition to the Form N-400, you will have to submit supporting documents. If you file your application online, you will have to upload electronic copies of each and every supporting document to your USCIS online account.

What are supporting documents?

Every applicant must include the following:

  • Copy of your Green Card (Form I-551, “Permanent Resident Card”)
  • Application fee(s) (Check, Money Order, or by Credit Card using Form G-1450)

Some applicants must submit additional documents based on their given situation, including:

  • Proof of your marital status, if you’re married or were previously married (Marriage Certificate, divorce papers, annulment certificate(s), and/or death certificate(s) for former spouses)
  • Two 2-inch x 2-inch passport-style photos, if you live and are applying from abroad. Using a pencil or felt pen, lightly print your name and A-Number (if any) on the back of the photo.
  • Form N-426, “Request for Certification of Military or Naval Service,” if you are applying for based on your military service (
  • Form N-648, “Medical Certification for Disability Exceptions,” if you are applying for an exemption to the U.S. Citizenship test based on a qualifying medical condition (

Form N-400 and gathering all necessary supporting documents is only a first step to becoming a U.S. citizen. However, completing the N-400 application form and gathering right documents at the first time will definitely avoid any undue delays. We, Lawfully, are here to guide you through to the end, including what to expect during the interview, and follow-up as to the status of your application.

For more N-400 and supporting documents related instructions , please see our Naturalization Documents page.

Try Lawfully to apply for U.S. citizenship!

4. Additional helpful information for naturalization applicants

Simple mistakes make the process a lot longer than it should be. It can even get your N-400 application denied entirely and make you start all over.

Check the below N-400 instructions and guide to help you through the naturalization application process.

Make Sure You DO

  1. Do use black ink ONLY. We recommend completing the form electronically then print it afterward. However, if you prefer to or do not have access to a computer, then make sure to use the BLACK INK pen.

  2. Do review your form N-400 application once again before filing. It is important to make sure that all of your answers are correct, and all supporting documents are included. Any missing information or incorrect answer may lead your application process a lot longer than it should. Worst case scenario, it could get the N-400 application to be denied,

    We, Lawfully, can review your N-400 application before filing. Lawfully will help your application package and get professional review by lawyers.

  3. Do provide certified translation. If any of the supporting documents are in a language other than English, must have translated and have it certified.

Make Sure You DON'T

  1. Don’t clutter the N-400 application form. Do not highlight, cross out, or write beyond the space provided. If you made a mistake and needs to correct it, it is better to redo the entire application.
  2. Don’t submit unnecessary documents. The Form N-400 instructions clearly indicate which documents must be submitted in original and in copies. If you mistakenly submit an original in which USCIS did not request for, you will not get that original back. So, make sure you submit all supporting documents according to the instructions.
  3. Don’t forget to sign. If you submit the form without signing it, USCIS will most likely reject your form N-400 and request to send a new one. If this is the case, you can lose your initial application fee and pay the fee once again.