2,000 in United States (1997 W. Meya), increasing. 2,300 L1 speakers of all Sioux dialects in a total population of 175,000. L2 users: 100 in United States (2016 W. Meya). Ethnic population: 170,000 (2016 W. Meya).

Canada: 100 (2016 Lakota Language Consortium). Ethnic population: 5,000 (2016 Lakota Language Consortium). Includes all ethnic Sioux.

6,200 in United States (R. Pustet 1997). Ethnic population: 20,000 (1987 SIL and R. Pustet 1997). 103,255 ethnic Sioux in USA (1990 Census Bureau).

Sioux is the cover term for the varieties of the Dakotan dialect complex other than Assiniboine and Stoney, with 3 dialect groups: Santee-Sisseton (Dakota), Yankton-Yanktonai, and Teton (Lakota). Teton (Lakota) is the dialect of the Cheyenne River, Lower Brule, Pine Ridge, Rosebud, and Sisseton Reservations of South Dakota, as well as of the southern part of the Standing Rock Reservation in South Dakota and of the Wood Mountain Reserve in Saskatchewan. There are also substantial off-reservation communities of Sioux speakers, particularly in Rapid City, Minneapolis, and other urban centers in the upper Midwest. Together, there are nearly 25,000 first-language speakers of all Sioux dialects in a total population of 103,000. Of these an estimated 4,755 reside in Canada.

Lakota is dangerously close to extinction. Recent linguistic surveys and anecdotal evidence reveal that there are only 2,000 first-language Lakota speakers remaining, on and around the reservations of North Dakota and South Dakota. This number represents less than 2% of the total Lakota population.