Dalfsen is a municipality and a town in the Salland region of the Dutch province of Overijssel. The municipality of Dalfsen was increased to its current size on 1 January 2001 through the amalgamation of the municipalities of Nieuwleusen and Dalfsen. A variety of Sallands is spoken here by segment of the population.

Salland is a historical dominion in the west and north of the present Dutch province of Overijssel. Nowadays Salland is usually used to indicate a region corresponding to the part of the former dominion more or less to the west of Twente.