Charlie Lake is situated 8 km west from Fort St. John, along the Alaska Highway. The lake provides the water supply for the city of Fort St. John. The lake is named after the Charlie Lake Formation, a geological stratigraphical unit of the Western Canadian Sedimentary Basin. 

The lake is situated at an elevation of 700 m (2,300 ft). It is formed along the Stoddart Creek, a right tributary of the Beatton River, itself a major tributary of the Peace River.

Two parks are established on the shores of the lake, Charlie Lake Provincial Park on the west shore, and Beatton Provincial Park on the east shore. The Charlie Lake settlement lies at the southern tip of the lake.