The route begins at PR 240 south of Portage la Prairie, and terminates at PTH 13 in Oakville.

PR 331 is mainly a straight east-west road, with one major winding section known as Hoop and Holler Bend.

This stretch of road skirts the southern banks of the Assiniboine River at around the midway point of the route.

Hoop and Holler Bend was used as a controlled breach in the midst of a major flood in the spring of 2011.

[2] Prior to this, PR 331 extended past its current eastbound terminus with PTH 13 for another 8 kilometres (5.0 mi) before terminating at the Trans-Canada Highway near the unincorporated community of Fortier.