A Guide to US Naturalization This Guide is to help people understand the naturalization process. It is for
people 18 years or older who want to become citizens.
How do I become a naturalized citizen?
If you are not a U.S. citizen by birth or did not acquire U.S. citizenship
automatically after birth, you may still be eligible to become a citizen through
the normal naturalization process. People who are 18 years and older use the “Application for Naturalization” (Form N-400) to become naturalized.
Persons who acquired citizenship from parent(s) while under 18 years of age
use the “Application for a Certificate of Citizenship” (Form N-600) to document
their citizenship. Qualified children who reside abroad use the “Application for
Citizenship and Issuance of Certificate under Section 322” (Form N-600K) to
document their naturalization. You may call the USCIS Forms Line at 1(800) 870-
3676 to request a Form N-400, N-600, or N-600K