Alingsås Municipality (Alingsås kommun) is a municipality in Västra Götaland County in western Sweden. Its seat is located in the city of Alingsås.
The present municipality was formed in 1974 then the former City of Alingsås (itself a municipality of unitary type since the subdivision reform of 1971) was amalgamated with Bjärke and Hemsjö.
Alingsås is part (together with 12 other municipalities) of the Gothenburg Metropolitan Area with 900 000 inhabitants. Alingsås municipality has today (2011-01-01) 37 825 inhabitants. Most people lives in Alingsås city (ca 25 000 inhab).
Alingsås has seven sister cities:
Coordinates: 57°56′N 12°32′E / 57.933°N 12.533°E / 57.933; 12.533