Source: FAA
If you own a drone, you must register it with the Federal Aviation Administration’s Unmanned Aircraft System (UAS) registry. A federal law effective December 21, 2015 requires unmanned aircraft registration, and you are subject to civil and criminal penalties if you do not register.
What’s covered by the new registration system?
Q. Who is required to register on the new online UAS registration website?
A. Only individual recreational or hobby users who meet U.S. citizenship requirements are able to register their unmanned aircraft using this new streamlined web-based process. This new, faster and easier system will be available for other UAS owners soon.
Q. Which unmanned aircraft may register under the new registration requirements?
A. Unmanned aircraft weighing less than 55 pounds and more than 0.55 pounds (250 grams) on takeoff, including everything that is on board or otherwise attached to the aircraft and operated outdoors in the national airspace system must register. These aircraft may register under the new web-based registration system.
More information can be found:
FAA website – http://www.faa.gov/uas/registration/