For filing US citizenship you need to apply form N-400. The filing fees for form N-400 is $595. An additional fee of $85 is required for biometric services. About biometrics, USCIS notifies the place and date after you have filled the application. Certain categories of people are exempted from the biometric fees. These are:
Applicants who are under military provisions and applying for citizenship are exempted from form filing fees as well as biometric fees.
The application fees needs to be submitted at the time of applying form N-400. Fees include both the form fees as well as the biometric fees. Thus, you need to single check or money order of $680 ($595 filling fees + $85 biometric fees).
Here are the guidelines which you need to follow while preparing your check or money order.
If you are making payment by check, it will be converted to electronic funds transfer at USCIS office. This means that they will use the account information on check to electronically debt the amount from your bank account. After successful transaction, they will not give you back the original check instead they will destroy it and keep the copy of your check with them.
While filing the form you need to make sure that it is accompanied with correct fees. If it is not, USICS will reject your form and return the fees with a reason why your form is rejected. Thereafter, you can reapply the form with correct fees.
USCIS changes fees periodically so it is required that you should verify the correct fees on their website before applying. For this you can check forms column on www.uscis.gov website or you may call USCIS customer center for fees information at 1-800-375-5283.