Whatì (; from the Dogrib language meaning "Marten Lakes"), officially the Tà Âñèchë Community Government of Whatì is a First Nations community in the North Slave Region of the Northwest Territories, Canada. Whatì is located by Lac La Martre, about northwest of the territorial capital of Yellowknife.
With rich and varied wildlife, the area has long been a favoured hunting ground of the Tà Âñèchë (Dogrib Dene) Indigenous people. The North West Company established a trading post there in 1793, and many natives began settling there permanently, while they continued to hunt and fish in the area. With the establishment of a trading post at Fort Rae on Great Slave Lake in the late 19th century, most regional trading was accomplished at the Hudson's Bay Company and free traders posts there. A trading post at Lac La Martre was not again established until the 1920s.
On January 1, 1996, the community officially changed its name from Lac La Martre to the Tà Âñèchë name "Wha Ti", meaning "Marten Lake," the same meaning as the French and then on August 4, 2005 to the current spelling. Other traditional Tà Âñèchë names for the settlement include Tsoti ('fouled water lake') and Mine Go Kola ('net fishing with houses').
Before 2005, the community was unincorporated, and local governance was provided by a First Nations band government, Wha Ti First Nation. Under the terms of the Tà Âñèchë Agreement, most responsibilities of Wha Ti have been transferred to a new Whatì Community Government. However, the First Nation is still recognized by the federal government for Indian Act enrollment.
In the 2021 Census of Population conducted by Statistics Canada, Whatì had a population of living in of its total private dwellings, a change of from its 2016 population of . With a land area of , it had a population density of in 2021.
The majority of the population is Indigenous of which 445 were First Nations and 10 were Métis. The main languages were Dogrib and English with a few North Slavey speakers.
While trapping, hunting, and fishing continue to be the main economic activities in this traditional community, efforts have been made to develop tourism as well. A fishing lodge was opened, and many tourists come to see the abundant wildlife, including black bears, barren-ground caribou, wolves, and eagles. The community takes special pride in the fact that no alcohol is allowed there.
Whatì is part of the Tlicho Government.
Whatì Airport connects the community by air to the territorial capital Yellowknife.
Whatì is connected to the territorial road network by the Tà Âñèchë Highway (Northwest Territories Highway 9), an all-season gravel road running from the community to the Yellowknife Highway (Northwest Territories Highway 3). The only road access to Whatì prior to the Tà Âñèchë Highway opening in 2021 was via winter road.
Telephone service was introduced to Whati in 1982.
Whatì has a subarctic climate (Köppen: Dfc; Trewartha: Ecld) with mild to warm summers and long cold winters.