Processing fees are always changing. However, currently, the processing fee to become naturalized, is $595 plus $85 for biometrics. A naturalization application is commonly referred to as an N-400. Attorneys typically charge between $1,000 – $1,500 for their services for this process which takes about 4 months to complete. Because fees are updated (meaning increased) on a regular basis by INS, you can verify this information by going to INS.gov.