
The Barents Sea is a marginal sea of the Arctic Ocean, located off the northern coasts of Norway and Russia and divided between Norwegian and Russian territorial waters. Known among Russians in the Middle Ages as the Murman Sea, the current name of the sea is after the historical Dutch navigator Willem Barentsz.
The Beaufort Sea is a marginal sea of the Arctic Ocean, located north of the Northwest Territories, the Yukon, and Alaska, and west of Canada's Arctic islands. The sea is named after Sir Francis Beaufort, a hydrographer. The Mackenzie River, the longest in Canada, empties into the Canadian part of the Beaufort Sea west of Tuktoyaktuk, which is one of the few permanent settlements on the sea's shores.

Chukchi Sea, sometimes referred to as the Chuuk Sea, Chukotsk Sea or the Sea of Chukotsk, is a marginal sea of the Arctic Ocean. It is bounded on the west by the Long Strait, off Wrangel Island, and in the east by Point Barrow, Alaska, beyond which lies the Beaufort Sea. The Bering Strait forms its southernmost limit and connects it to the Bering Sea and the Pacific Ocean. The principal port on the Chukchi Sea is Uelen in Russia. The International Date Line crosses the Chukchi Sea from northwest to southeast. It is displaced eastwards to avoid Wrangel Island as well as the Chukotka Autonomous Okrug on the Russian mainland.

The Greenland Sea is a body of water that borders Greenland to the west, the Svalbard archipelago to the east, Fram Strait and the Arctic Ocean to the north, and the Norwegian Sea and Iceland to the south. The Greenland Sea is often defined as part of the Arctic Ocean, sometimes as part of the Atlantic Ocean. However, definitions of the Arctic Ocean and its seas tend to be imprecise or arbitrary. In general usage the term "Arctic Ocean" would exclude the Greenland Sea. In oceanographic studies the Greenland Sea is considered part of the Nordic Seas, along with the Norwegian Sea. The Nordic Seas are the main connection between the Arctic and Atlantic oceans and, as such, could be of great significance in a possible shutdown of thermohaline circulation. In oceanography the Arctic Ocean and Nordic Seas are often referred to collectively as the "Arctic Mediterranean Sea", a marginal sea of the Atlantic.

Hudson Bay is a large body of saltwater in northeastern Canada with a surface area of 1,230,000 km2 (470,000 sq mi). Although not geographically apparent, it is for climatic reasons considered to be a marginal sea of the Arctic Ocean. It drains a very large area, about 3,861,400 km2 (1,490,900 sq mi), that includes parts of southeastern Nunavut, Alberta, Saskatchewan, Ontario, Quebec, all of Manitoba and indirectly through smaller passages of water parts of the U.S. states of North Dakota, South Dakota, Minnesota, and Montana. Hudson Bay's southern arm is called James Bay.

The Kara Sea is part of the Arctic Ocean north of Siberia. It is separated from the Barents Sea to the west by the Kara Strait and Novaya Zemlya, and from the Laptev Sea to the east by the Severnaya Zemlya archipelago. It is named after the Kara River, which is now relatively insignificant but which played an important role in the Russian conquest of northern Siberia. The Kara River name is derived from a Nenets word meaning "hummocked ice".

Lincoln Sea is a body of water in the Arctic Ocean, stretching from Cape Columbia, Canada, in the west to Cape Morris Jesup, Greenland, in the east. The northern limit is defined as the great circle line between those two headlands. It is covered with sea ice throughout the year, the thickest sea ice in the Arctic Ocean, which can be up to 15 m (49 ft) thick. Water depths range from 100 m (330 ft) to 300 m (980 ft). Water and ice from Lincoln Sea empty into Robeson Channel, the northernmost part of Nares Strait, most of the time.

The Nordic Seas are located north of Iceland and south of Svalbard. They have also been defined as the region located north of the Greenland-Scotland Ridge and south of the Fram Strait-Spitsbergen-Norway intersection. Known to connect the North Pacific and the North Atlantic waters, this region is also known as having some of the densest waters, creating the densest region found in the North Atlantic Deep Water. The deepest waters of the Arctic Ocean are connected to the worlds other oceans through Nordic Seas and Fram Strait. There are three seas within the Nordic Sea: Greenland Sea, Norwegian Sea, and Iceland Sea. The Nordic Seas only make up about 0.75% of the World’s Oceans. This region is known as having diverse features in such a small topographic area, such as the mid oceanic ridge systems. Some locations have shallow shelves, while others have deep slopes and basins. This region, because of the atmosphere-ocean transfer of energy and gases, has varying seasonal climate. During the winter, sea ice is formed in the western and northern regions of the Nordic Seas, whereas during the summer months, the majority of the region remains free of ice.

The Open Polar Sea was a hypothesized ice-free ocean surrounding the North Pole. This unproved and eventually-disproved theory was once so widely believed that many exploring expeditions used it as justification for attempts to reach the North Pole by sea or to find a navigable sea route between Europe and the Pacific across the North Pole.
Pechora Sea, is a sea at the northwest of Russia, the southeastern part of the Barents Sea. The western border of the sea is off Kolguyev Island, while the eastern border is the western coasts of Vaygach Island and the Yugorsky Peninsula, and the northern border the southern end of Novaya Zemlya.

The Wandel Sea is a body of water in the Arctic Ocean, stretching from northeast of Greenland to Svalbard. It is obstructed by ice most of the year.

The White Sea is a southern inlet of the Barents Sea located on the northwest coast of Russia. It is surrounded by Karelia to the west, the Kola Peninsula to the north, and the Kanin Peninsula to the northeast. The whole of the White Sea is under Russian sovereignty and considered to be part of the internal waters of Russia. Administratively, it is divided between Arkhangelsk and Murmansk oblasts and the Republic of Karelia.