The Northwest Territories^[b] is a territory of Canada. At a land area of approximately 1,127,711.92 square kilometres (435,412.01 sq mi) and a 2026 estimated population of 45,808, it is the second-largest and second-most populous of the three territories in Northern Canada.^[5] Under its modern borders, the Northwest Territories consists of a large part of Denendeh—traditional land of the Dene—and most of the Inuvialuit Settlement Region (known as Inuvialuit Nunangit Sannaiqtuaq in Inuinnaqtun)—traditional land of the Western Canadian Inuit. The territory also contains some land traditionally used by Cree and Métis peoples. Its capital and most populous community is Yellowknife, the only city in the territory; its population was 20,340 as of the 2021 census. It became the territorial capital in 1967, following recommendations by the Carrothers Commission.

The territory entered Canadian Confederation on July 15, 1870, replacing most of British North America‘s regions of North-Western Territory, Rupert’s Land and, after 1880, the British Arctic Territories. At that time, it consisted of a vast but sparsely populated area covering a majority of modern Canada’s land area, including most of Nunavut, the Canadian Prairies, Northern Ontario, Northern Quebec and Labrador. Since 1870, the territory has been divided four times to create new provinces and territories or enlarge existing ones. Its current borders date from April 1, 1999, when the territory’s size was decreased again by the creation of a new territory of Nunavut to the east.^[12][13]

While Nunavut is mostly Arctic tundra, the Northwest Territories has a slightly warmer climate and is both boreal forest (taiga) and tundra, and its most northern regions form part of the Arctic Archipelago.

The Northwest Territories has the most interprovincial and inter-territorial land borders among all provinces and territories of Canada. It is bordered by the territories of Nunavut to the east and Yukon to the west, and by the provinces of British Columbia, Alberta, and Saskatchewan to the south; it also touches Manitoba to the southeast at a quadripoint that includes Nunavut and Saskatchewan. The land area of the Northwest Territories is roughly equal to that of France, Portugal and Spain combined, although its overall area is even larger because of its vast lakes.