A United States citizenship application is filed on USCIS form N-400 (Application for Naturalization) by mailing the completed forms and required documents to one of two lock box facilities, based upon the applicant’s state of residence. After the citizenship application is processed, the local USCIS office will schedule a citizenship interview and complete the naturalization process. Citizenship application processing times will vary by local office.
Express/Courier: USCIS Attn: N-400 1820 E Skyharbor Circle S Suite 100 Phoenix, AZ 85034
Express/Courier: USCIS Attn: N-400 2501 S State Hwy 121 Suite 400 Lewisville, TX 75067
Military Applications If filing from N-400 under INA 328 or INA 329, file at the Nebraska Service Center regardless of where you reside: Nebraska Service Center P.O. Box 87426, Lincoln NE 68501-7426
ArizonaUSCIS P.O. Box 21251 Phoenix, AZ 85036