Form N-400: Application for Naturalization

What is the N-400 Citizenship Form?

The **N-400 citizenship form** is the application used by lawful permanent residents to apply for U.S. citizenship. Submitting this **naturalization application** starts the final legal process of transitioning from a green card holder to a full U.S. citizen.

To be eligible, you must be at least 18 years old and prove that you have lived in the U.S. as a permanent resident for at least 5 years (or 3 years if you are married to a U.S. citizen).

How to Apply for Citizenship

To learn **how to apply for citizenship**, you must verify that you meet the continuous residence and physical presence requirements. You must have been physically present in the United States for at least 30 months out of the 5 years before filing.

USCIS allows you to file the Form N-400 up to 90 days before you reach your 3-year or 5-year permanent residency anniversary date.

Where Do You File Form N-400?

You can file Form N-400 either online or by mailing a physical paper application.

Filing online is highly recommended because it immediately checks for errors, allows you to upload supporting documents, pay fees securely, and communicate with USCIS officers.

Filing Fees & Processing Times

Filing Fee: Naturalization applications require a base filing fee and a biometrics service fee. Check the official uscis.gov/forms page for current rates as fees change regularly.

Processing Time: Processing takes 6 to 12 months on average. Timeline lengths depend on the local USCIS field office serving your metropolitan area.

Common Mistakes to Avoid

• Filing Too Early: Sponsoring residents must not file earlier than the 90-day window before their anniversary date. Filing even one day early leads to automatic denial and loss of fee.
• Inaccurate Travel Logs: You must list every single trip outside the United States that lasted 24 hours or longer. Guessing travel dates can look like misrepresentation.
• Unpaid Taxes or Child Support: Sponsoring residents must demonstrate "good moral character." Unpaid federal taxes or child support obligations can lead to visa rejection.

What Happens After You File?

USCIS will mail you a receipt notice. Next, you may have to go to a USCIS site for a biometrics fingerprinting appointment.

You will then receive an interview notice. During the interview, you must pass the English reading and writing tests and a U.S. history and civics test. Once passed, you will attend an oath ceremony to take the Oath of Allegiance and receive your naturalization certificate.

Frequently Asked Questions