Halsa is a former municipality in Møre og Romsdal county, Norway. The municipality existed from 1838 until 2020 when it became part of Heim Municipality in Trondelag county. It was part of the Nordmøre region. The administrative centre of Halsa was the village of Liabøen. Other villages in the municipality included Betna, Hennset, Klevset, Todalen, Halsa, Valsøyfjord, Engan, Hjellnes, and Valsøybotn.

Prior to its dissolution in 2020, the 301-square-kilometre (116 sq mi) municipality was the 279th largest by area out of the 422 municipalities in Norway. Halsa Municipality was the 349th most populous municipality in Norway with a population of 1,574. The municipality's population density was 5.2 inhabitants per square kilometre (13/sq mi) and its population has decreased by 4.4% over the previous 10-year period.

The parish of Halsa was established as a municipality on 1 January 1838 (see formannskapsdistrikt law). On 1 January 1868, an unpopulated area of Halsa Municipality was transferred to the neighboring Straumsnes Municipality. On 1 January 1879, a part of Halsa Municipality (population: 279) was transferred to the neighboring Stangvik Municipality. The next year, the Torjulvågen area (population: 240) on the west side of the Halsafjorden was transferred to Tingvoll Municipality. On 1 July 1915, part of southern Halsa Municipality (population: 114) was transferred to Åsskard Municipality.

During the 1960s, there were many municipal mergers across Norway due to the work of the Schei Committee. On 1 January 1965, all of Valsøyfjord Municipality that was located on the mainland (population: 1,104) was merged into Halsa Municipality. On 1 January 1976, the district of Aure Municipality located south of the Vinjefjorden (population: 158) was transferred to Halsa Municipality.

On 1 January 2020, Halsa Municipality merged with the neighboring Hemne Municipality and the Ytre Snillfjord area of Snillfjord Municipality to form the new Heim Municipality. Heim Municipality is located in Trøndelag county, which means that as part of the merger, Halsa Municipality left Møre og Romsdal county and moved to Trøndelag county.

The municipality (originally the parish) is named after the old Halsa farm (Old Norse: Hǫlsyinjar) since the first Halsa Church was built there. The first element comes from the plural form of the word hals which means "neck". Here, the word hals is referring to an isthmus (or neck of land) between two fjords: Halsafjorden and the Skålvikfjorden. The last element is vin which means "meadow" or "pasture". Historically, the name of the municipality was spelled Halse. On 3 November 1917, a royal resolution changed the spelling of the name of the municipality to Halsa.

The coat of arms was granted on 19 August 1988 and it was in use until 2020 when the municipality ceased to exist. The official blazon is "Per bend sinister embattled argent and azure" (Norwegian: Venstre skrådelt av sølv og blått ved tindesnitt). This means the arms have are divided with a diagonal line that is embattled. The field (background) below the line has a tincture of azure. Above the line, the field has a tincture of argent which means it is commonly colored white, but if it is made out of metal, then silver is used. The embattled line symbolizes the municipal coastline since there are three fjords (Halsafjorden, Skålvikfjorden and Valsøyfjorden) protruding inland from the north coast of the municipality. The arms were designed by Asbjørn Heggem. The municipal flag has the same design as the coat of arms.

The Church of Norway had two parishes (sokn) within Halsa Municipality. It was part of the Indre Nordmøre prosti (deanery) in the Diocese of Møre.