A gambling ship is the term for a ship stationed offshore in or transiting to international waters to evade local anti-gambling laws that is dedicated to games of chance. This applies both to ships which are permanently moored somewhere outside the limits, or, when legal, that can transit back and forth from a nearby port where it is not. Other ships also offer gambling as part of their onboard entertainment, but are not "gambling ships" per se.
Historically, international waters began just 3 miles (4.8 km) from land in many countries, popularly referred to as the "three-mile limit". Gambling ships, like offshore radio stations, would usually be anchored just beyond it.[1] The redefinition of territorial waters to 12 nautical miles—approximately 13.8 miles (22.2 km)— in 1982 made maintaining a gambling ship much more uneconomic.
In the United States, in addition to federal law, states statues regulate the legality of gambling ships in their waters.[2]