“Biometrics” is just a technical term for your fingerprints, plus photos and/or signature. USCIS typically schedules the required biometrics appointment about one month after it receives your U.S. citizenship application. You’ll receive an appointment letter (Form I-797C, officially called the “Notice of Action”) from USCIS specifying when and where your fingerprints, photos, and signature will be collected. These will be used to verify your identity. USCIS will also forward your fingerprints to the Federal Bureau of Investigation (FBI) to conduct a background check.
In order to avoid needing to return for a second biometrics appointment, it’s important to bring all required documentation with you the first time. These documents include your appointment letter, Permanent Resident Card (your “green card”), and second form of ID with your photo (driver’s license, passport, or state ID).
Sometimes, however, a second biometrics appointment is necessary for other reasons. In the relatively unlikely event that the FBI rejects your fingerprints, for instance, USCIS will send you a new appointment letter to take a second set of fingerprints. If the FBI rejects the second set, you’ll need to obtain a police clearance certificate from the police department at each of the places where you’ve lived in the past five years and send these to the FBI. If necessary, it’s best to start gathering these certificates quickly after receiving instructions from the FBI, as police departments handle such requests at different speeds.
During this stage of the process, it’s also possible to receive a notice from USCIS requesting additional information or materials, which will be specified in a letter (officially called a “Request for Evidence,” or RFE). These documents could be court or police records (if USCIS discovers information during the background check that needs clarification or substantiation, for instance). There could also be other required documents listed in this checklist from USCIS. Make sure to send these to USCIS as soon as possible to minimize the delay.