Balsfjord (Northern Sami: Báhccavuotna or Kven: Paatsivuono) is a municipality in Troms county, Norway. The administrative centre of the municipality is the village of Storsteinnes. Other villages include Mestervik, Mortenhals, and Nordkjosbotn.
The municipality surrounds two fjords: Malangen and Balsfjorden, surrounded by comparatively rich farmlands under majestic peaks including the southern end of the Lyngen Alps.
Balsfjord was originally a part of the great Tromsøe landdistrikt municipality, but it was separated from this in 1860 to form its own municipality. Balsfjord had an initial population of 3,610. On 1 January 1871, Malangen (population: 1,425) was separated from it, leaving Balsfjord with 2,255 inhabitants. On 1 January 1875, a part of Lyngen (population: 7) was transferred to Balsfjord. On 1 January 1905, a part of Balsfjord (population: 5) was transferred to Målselv.
On 1 January 1964, most of Balsfjord was merged with most of neighboring Malangen to form a new, larger municipality of Balsfjord (population: 6,993). Also on that day, the Skogli ved Heia area (population: 2) was transferred to Målselv and the uninhabited Elvebakken farm was transferred to Storfjord. On 1 January 1966, the Sørelvmo area of Balsfjord (population: 131) was transferred to Målselv.