Borlänge Municipality is a municipality in Dalarna County in central Sweden, with an area of 586.4 km2. The municipality has a population of 47,640 (2007). The municipal seat is Borlänge.

Dalarna County is a county or län in central Sweden (Svealand). It borders on the counties of Uppsala, Jämtland, Gävleborg, Västmanland, Örebro and Värmland. It also borders on the Norwegian counties of Hedmark and Trøndelag to the west. It was formerly known as Kopparberg County until the name was changed to that of the provincial region on 1 January 1997. The province of Dalarna is slightly larger than the county, as the westernmost part of Ljusdal Municipality belongs to it. Prince Gabriel, the son of Prince Carl Philip, is Duke of Dalarna.