Fillable N-400 Application for Naturalization – Download & Complete Online

The N-400, Application for Naturalization is the official United States Citizenship and Immigration Services (USCIS) form used by permanent residents to apply for U.S. citizenship. With Formize you can download the exact PDF used by USCIS and fill it out instantly in your browser—no extra software required.

What Is the N-400 Form?

The N-400 collects personal information, residency history, employment details, and questions about your moral character. It also includes sections for the English and civics tests, exemptions, and any supporting documentation you must attach.

How to Fill Out the N-400 with Formize

Our simple, step‑by‑step process lets you complete the form in minutes:

1. Click the "Fill out this form" button below.
2. Wait a few seconds while the Formize PDF Filler app loads the official N-400 PDF.
3. Enter your answers directly into the fillable fields. The interface saves your progress automatically.
4. When you’re done, download the completed PDF or submit it electronically according to USCIS instructions.

Common Mistakes to Avoid When Completing N-400

• Using the wrong edition: Ensure the PDF shows the edition date 01/20/25 (the current version).
• Leaving required fields blank: Every field marked with an asterisk (*) must be completed, even if the answer is "None" or "N/A".
• Incorrect dates or formats: Use mm/dd/yy for all dates as USCIS requires.
• Submitting original documents: Only attach copies unless USCIS specifically asks for originals.
• Missing signatures: The form is invalid without the applicant’s signature and the date.

Where to Submit Your Completed N-400

After filling out the form, you can either file it online through your USCIS account or print the PDF and mail it to the appropriate USCIS lockbox address. The filing fee and any required supporting documents must accompany the form.

Need more guidance? Review the official USCIS N-400 PDF and the accompanying instructions for detailed eligibility criteria.