Cumberland Sound (French: Baie Cumberland; Inuit: Kangiqtualuk) is an Arctic waterway in Qikiqtaaluk Region, Nunavut, Canada. It is a western arm of the Labrador Sea located between Baffin Island's Hall Peninsula and the Cumberland Peninsula. It is approximately 250 km (160 mi) long and 80 km (50 mi) wide. Other names are Cumberland Straits, Hogarth Sound, and Northumberland Inlet. Old Norse is ᚠᛁᛋᚦᚱᛁ ᚢᛒᚢᚴᚦᛁᛦ, fisþri ubukþiR.
The only settlement located on the shore of the sound on the Cumberland Peninsula is Pangnirtung.
John Davis, the English explorer, went part way up the sound in 1585. After that it was unvisited by Europeans until 1839, when the British whaler and explorer William Penny persuaded Eenoolooapik (brother of interpreter and guide Taqulittuq) to show him the inland sea. The Inuk had described the sound, known to him as Tenudiackbeek, as full of whales, and soon the British set up a whaling station there.
The bay is home to the Cumberland Sound beluga whale, a species known to reside year-round in the sound, with summers spent at the northern end. As well as ringed, bearded, harp, harbour and hooded seals, there are Arctic char, Greenland halibut, and other fish. Birds such as gulls, ducks, and geese also migrate and spend the spring and summer in Cumberland Sound, and ptarmigan and ravens remain year-round.