The remote-controlled aircraft vary in size and form, with some being as small as model airplanes and others as large as military Predators.
Local and state law enforcement agencies are expected to be the largest customers of the drones.
The issue has increased public concern over violations of privacy.
The use of assassination drones overseas under the administration of US President Barack Obama has caused a national debate.
Washington has used its assassination and surveillance drones in several countries including Yemen, Pakistan, and Somalia.
As concerns grow over the violation of privacy in the United States, the Federal Aviation Administration (FAA) says it has issued hundreds of permits for domestic drone operators.
On Friday, the FAA said it had issued some 1,428 permits since 2007, a number much greater than previously known. Some 327 permits are still listed as active.
Domestic drone operators include the police department, universities, state transportation departments, and at least seven other federal agencies including the CIA.
The FAA also says another 10,000 drone permits could be issued over the next five years in an effort to license more surveillance drones in US airspace.