Atlantic halibut are distributed widely throughout the northern Atlantic. In the northwestern Atlantic, populations are found from the coast of Virginia to as far north as the Arctic Circle. Significant numbers swim off the coasts of Greenland, Newfoundland and Labrador, the Gulf of St. Lawrence, and Nova Scotia. In the northeast, Atlantic halibut range from the Bay of Biscay to Spitsbergen and the Barents Sea. Atlantic halibut are a popular game fish and are fished commercially.

Atlantic halibut have a compressed, oval-shaped body and usually have both eyes on the right side of their bodies with the left side being totally blind. They are greenish-brown to almost black on their eyed side. Juveniles might be slightly spotted or flecked and have white undersides, which become mottled with grey or reddish spots as they mature. Their mouths are very large and have numerous sharp curved teeth. Atlantic halibut may grow to a length of more than two metres though they typically weigh less than 100 kg.