With a few exceptions, cruise casinos are not open while ships are in port. They are generally limited to operating while the ship is in international waters.

Generally, you cannot gamble on a cruise ship while it is docked in port. Most cruise ship casinos are required by international maritime law and local coastal regulations to remain closed whenever the ship is within the territorial waters of a country. The casino typically opens only when the ship reaches international waters, which is usually about 3 to 12 nautical miles (roughly 5.5 to 22 kilometers) away from the coastline. This is because the ship must comply with the gambling laws of the country it is visiting, and many nations either prohibit gambling or require specific, expensive licenses that cruise lines do not maintain for short visits. There are very rare exceptions, such as in certain ports in Bermuda or Malta where local authorities have granted special permission for casinos to operate during overnight stays, but these are infrequent. For most itineraries, the casino staff will use port time to rest or perform maintenance, and the "slots" and tables will only roar back to life once the ship has safely cleared the harbor and returned to the open sea.