The fee for an application for naturalization is payable by personal check, cashier's check, money order or credit card, accompanied by the appropriate form, according to U.S. Citizenship and Immigration Services. Checks or money orders must be payable to the Department of Homeland Security and mailed with the application form.
The total fee for a citizenship application consists of a filing fee and a biometric fee, notes USCIS. Applicants over the age of 75 are exempt from the biometric fee and must only pay the filing fee, as of 2015. Military members applying under Section 328 and 329 of the Immigration and Nationality Act are exempt from any application fees.