It was formed in 2008 out of parts of Penticton-Okanagan Valley, West Kootenay-Boundary and Yale-Lillooet.

[1] Due to the realignment of electoral boundaries, most incumbents did not represent the entirety of their listed district during the preceding legislative term.

was the MLA for West Kootenay-Boundary, while Harry Lali, NDP, was the MLA for Yale-Lillooet (the areas of those ridings added to Boundary-Similkameen are less-populated and were not main population centres in their ridings).

The original riding of Boundary-Similkameen was a provincial electoral district in the Canadian province of British Columbia.

The 1988 byelection, which elected NDP member Bill Barlee, was the last appearance of the Boundary-Similkameen riding until its recreation in 2009.