North America: Atlantic, Arctic, and Pacific basins from northern Canada and Alaska south to New England in USA, Great Lakes, and northern Montana, USA. Introduced widely to many areas outside its native range.

Splakes (hybrid between Salvelinus namaycush and Salvelinus fontinalis) have also been successfully introduced to many areas of North America. The three observed phenotypes existing in Lake Superior (lean, siscowet and humper or paperbelly) are under some genetic control and not merely expressions of environmental adaptation (Ref. 40529).