If you haven’t already registered your drone with the federal government, better do so today or be prepared to face tough penalties.

Civil penalties for not registering your flying robots could be as high as $27,500. Criminal violations could cost you $250,000 in penalties plus a three-year prison sentence.

The registration rules apply to anyone over the age of 13 who owns a drone that weighs over half a pound. Some of the miniature drones that don’t require registration include the TSQ Heli Max and the Air Hogs Helix X4 Stunt, according to an Federal Aviation Administration document on drone weight guidance.

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It costs $5 dollars to register in the government system, and the registration lasts for three years. When you register, you will be issued a registration number, which you must mark somewhere on your drone. The registration number can be used for multiple drones so you don’t need to register more than once.

The FAA created the drone registration system in December as a way to better track drone pilots who may recklessly fly their aircraft in no-fly or unsafe areas, like an airport, for example.

Drone owners who registered their aircraft before January 21 were able to receive a $5 rebate.

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As of Friday, the FAA said that over 342,000 drones owners have registered in the government’s system. In early January, just a few weeks after the registration system came online, the FAA said that there were 181,000 registrations.