Factsheet: Zones of Maritime Jurisdiction


The United Nations Convention on the Law of the Sea (UNCLOS) is an international agreement that was concluded in 1982 and entered into force in 1994. The convention contains a regime for governing the world’s oceans, outlining the rights and responsibilities of states. One of the most important functions of the convention is to define different zones of maritime jurisdiction. States enjoy different rights within these zones, including navigational rights and resource exploration rights. Where these zones overlap, disputes can arise. The most common kind of disputes concerns overlapping exclusive economic zones, when the distance between two states is less than 400 nautical miles. The foundation for determining these zones is known as a baseline, which is usually the low-water mark along a state’s coastline or insular (land) feature. The zones are: Internal waters This zone refers to the waters on the landward side of the baseline. Coastal states enjoy effective sovereignty over these waters, including the rights to any resources in the water column or seabed. Innocent passage of foreign vessels is prohibited. Territorial waters This zone extends seaward 12 nautical miles from a state’s baselines. The coastal state enjoys effective sovereignty over this zone. Innocent passage of foreign vessels is permitted. Contiguous zone This zone exists between 12 and 24 nautical miles from a state’s baselines. States can enforce customs, taxation, immigration, and pollution laws in this zone. Freedom of navigation and overflight by foreign vessels is permitted. Exclusive economic zone This zone extends from 12 to 200 nautical miles from a state’s baseline. The coastal state enjoys exclusive exploration rights to the resources in the water column and seabed. Freedom of navigation and overflight by foreign vessels is permitted. Extended continental shelf A state’s continental shelf refers to the natural prolongation of territory to the outer edge of the continental margin. When the continental shelf exceeds 200 nautical miles, the coastal state enjoys exclusive rights to the minerals in the seabed. Freedom of navigation and overflight by foreign vessels is permitted.