Which agency conducts background investigations for security clearance?

The U.S. Office of Personnel Management (OPM) is responsible for conducting background investigations for security clearance. OPM undertakes thorough evaluations to determine an individual's suitability for access to classified information. These investigations involve reviewing a candidate’s personal history, including employment records, educational background, financial history, and criminal activity, to ascertain trustworthiness and reliability.

While other agencies like the Department of Defense (DOD) and the FBI play roles in the overall security clearance process — with the DOD being a significant end-user of cleared personnel and the FBI conducting background checks as part of the investigative process — OPM is the agency officially designated to conduct these background investigations. The CIA, primarily focused on intelligence and covert operations, does not engage in the broad authority of conducting security clearance background checks as part of its regular operations.