The Saskatchewan River (Cree: kisiskāciwani-sīpiy ᑭᓯᐢᑳᒋᐊᐧᓂ ᓰᐱᕀ, "swift flowing river") is a major river in Canada. It stretches about from where it is formed by the joining together of the North Saskatchewan and South Saskatchewan Rivers to Lake Winnipeg. It flows roughly eastward across Saskatchewan and Manitoba to empty into Lake Winnipeg. Through its tributaries the North Saskatchewan and South Saskatchewan, its watershed encompasses much of the prairie regions of Canada, stretching westward to the Rocky Mountains in Alberta and north-western Montana in the United States.
Including its tributaries, it reaches to its farthest headwaters on the Bow River, a tributary of the South Saskatchewan in Alberta.
It is formed in central Saskatchewan, approximately east of Prince Albert, by the confluence of its two major branches, the North Saskatchewan and the South Saskatchewan, at the Saskatchewan River Forks. Both source rivers originate from glaciers in the Alberta Rockies. The St. Mary River, draining the Hudson Bay Divide region of Glacier National Park (U.S.), also empties into the Saskatchewan River via the south fork.
The combined stream flows east-northeast, into Codette Lake formed by the Francois Finlay Dam at Nipawin then into Tobin Lake, formed by the E.B. Campbell Dam. It then flows northeast, passing through a region of marshes, where it is joined from the northwest by the Torch River and the Mossy River. At the northern edge of the marshes it flows east, twisting between a series of small lakes into west-central Manitoba to The Pas, where it is joined from the southwest by the Carrot River. Southeast of The Pas, it forms several streams in a delta on the northwest side of Cedar Lake, then exiting the lake on its southeast end and flowing approximately to Lake Winnipeg, entering on the northwest shore north of Long Point. The waters of Lake Winnipeg eventually drain into Hudson Bay, via the Nelson River.
The river, like the province of Saskatchewan, takes its name from the Cree word kisiskāciwani-sīpiy, meaning "swift flowing river".