Östersund Municipality, Administrative municipality in Jämtland County, northern Sweden.

Östersund Municipality is a Swedish municipality in Jämtland County whose seat, Östersund, is also the county seat. It was formed in 1971 by merging the City of Östersund with five surrounding rural municipalities. The terrain is gently undulating sedimentary bedrock covered with clay- and lime-rich moraine, drained by the Indalsälven, Hårkan and Långan rivers and including part of Lake Storsjön with the island of Frösön.

The municipality was established in 1971 when the city of Östersund merged with several surrounding rural villages to create a more efficient administrative structure. This consolidation was part of a larger Swedish reform movement that brought many similar mergers across the country.

The municipality's name appears in Southern Sami as Staaren tjïelte, and since 2010 it has belonged to the Sami administrative area. Council elections are held every four years alongside the national vote; in 2022 the left bloc took 58.5% of the vote in the municipality.

The municipality surrounds Storsjön and includes Frösön, linked to Östersund by bridge. Roads and buses connect the main town with surrounding parishes, but services thin out in rural areas. Ferries run to the lake islands, and trains stop in Östersund. Winter snow and ice affect travel from November to April.

The municipality's name has a Southern Sami form, Staaren tjïelte, and since 2010 it has belonged to the Sami administrative area. The arms of Östersund depict a moose head, a reference to Jämtland's hunting traditions.