US Citizenship Form

To become a U.S. citizen through naturalization, you will need to complete and file the U.S. citizenship form, N-400, Application for Naturalization. This form is required by U.S. Citizenship and Immigration Services (USCIS) and consists of 20 pages. You will need to complete the form in its entirety, submit supporting documentation, and a filing fee.

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Intro to U.S. Citizenship

If you do not qualify for automatic citizenship (citizenship by birth or by parents), then you may be eligible to apply for citizenship through naturalization. In most cases, you must first have a green card (permanent residence) for several years in order to be eligible. Beyond that, there are nine basic requirements to qualify for naturalization.

  1. Be at least 18 years old at the time of filing Form N-400, Application for Naturalization.
  2. Be a permanent resident (green card holder) for at least 5 years (3 years if married to a U.S. citizen).
  3. Show that you have lived for at least 3 months in the state or USCIS district where you apply.
  4. Demonstrate continuous residence in the U.S. for at least 5 years immediately preceding the date of filing Form N-400 (3 years if married to a U.S. citizen).
  5. Show that you have been physically present in the U.S. for at least 30 months out of the 5 years immediately preceding the date of filing Form N-400 (18 months over a 3-year period if married to a U.S. citizen).
  6. Be able to read, write, and speak basic English.
  7. Have a basic understanding of U.S. history and government (civics).
  8. Be a person of good moral character.
  9. Demonstrate an attachment to the principles and ideals of the U.S. Constitution.12

Form N-400, U.S. Citizenship Form

The citizenship form, Form N-400, is the longest USCIS application. The application itself is 20 pages long, plus 18 pages of instructions. It is important that you carefully read the questions and the instructions, as they are not always straightforward. Your reason for eligibility will determine how you answer certain questions and may require you to omit (not answer) other questions.

The questions are regarding:

  • Eligibility for citizenship
  • Current and past residences
  • Family history
  • Work history
  • Biographic information
  • Employment history
  • Education history
  • Time spent outside of the U.S. during your permanent residency
  • Marital history
  • Questions relating to your moral character3

N-400 Filing Fee

As of September 2018, the filing fee for the N-400 application is $640. Most applicants will also be required to pay a biometric services fee of $85 for a total of $725. When you send your N-400 application to the USCIS, include a check or money order with this application fee. Alternatively, you can pay using a credit card but will need to include an additional form, the G-1450, Authorization for Credit Card Transaction.4

If you are unable to submit the filing fee, the USCIS does have an income-based fee-waiver you may submit. You must be a qualifying applicant. To be eligible for a fee waiver, you must meet one of the following conditions:

  • You, your spouse, or the head of household living with you, are currently receiving a means-tested benefit (SNAP or food stamps, TANF, SSI, etc.).
  • Your household income is at or below 150 percent of the Federal Poverty Guidelines at the time you file. Check the current Federal Poverty Guidelines for this year at Form I-912P, HHS Poverty Guidelines for Fee Waiver Requests.
  • You are currently experiencing financial hardship that prevents you from paying the filing fee, including unexpected medical bills or emergencies.5

If you find yourself eligible, you may request that the USCIS waive the fee by submitting Form I-912 with your N-400 application. Note, the USCIS may deny the fee waiver at which point you will be required to submit the filing fee.

US citizenship filing instructions

After you complete the N-400 application, you will need to gather any necessary supporting documentation. Supporting documents are documents that prove your eligibility for citizenship.

Which supporting documents you send depends on your individual circumstances. To determine which documents you need, read the N-400 application instructions or choose a service to help you. provides excellent services for a fee, as well as customized filing instructions so you know exactly which documents to send to the USCIS.

The USCIS also requires that you submit:

  • A photocopy of both sides of your green card
  • Two passport-style photographs

Once your application package is complete, send it to the USCIS. Where you send your application depends on where you live. Check the USCIS website for the most up to date information.