Nes is a municipality in Buskerud county, Norway. It is part of the traditional region of Hallingdal. The administrative centre of the municipality is the village of Nesbyen.The parish of Næs was established as a municipality on 1 January 1838 (see formannskapsdistrikt). The area of Flå was separated from Nes on 1 January 1905 to become a separate municipality.
The municipality (originally the parish) is named after the old Nes farm (Old Norse: Nes—now the village of Nesbyen), since the first church was built there. The name is identical with the word nes which means headland". Prior to 1889, the name was spelled "Næs".The coat-of-arms is from modern times. They were granted on 29 June 1979. The arms show a yellow-gold triangle pointing to the left on a red background. This represents a sandy peninsula or headlands (yellow triangle) formed by the confluence of two rivers: Rukkedøla and Hallingdalselva. The design is canting because this is what the name of the municipality means (see above under the name).