Vadsø (Norwegian: [ˈvɑ̂dsøː] ⓘ; Northern Sami: Čáhcesuolu; Kven: Vesisaari) is a municipality in Finnmark County, Norway.

Other settlements in Vadsø include Ekkerøy, Kiby, Krampenes, Skallelv, Valen, and Vestre Jakobselv.

The law required that all towns should be separated from their rural districts, but because of a low population and very few voters, this was impossible to carry out for the municipality of Vadsø in 1838.

On 1 January 1894, the rest of the rural district (population: 1,296) surrounding the town of Vadsø was separated to form the new Nord-Varanger Municipality.

[7] On 1 January 2020, the municipality became part of the newly formed Troms og Finnmark county.

The official blazon is "Gules, a reindeer's head couped argent" (Norwegian: På rød bunn et hvitt reinbukkhode).

This means the arms have a red field (background) and the charge is the head of a reindeer stag.

The reindeer head has a tincture of argent which means it is commonly colored white, but if it is made out of metal, then silver is used.

Township privilege was granted in 1833, and soon settlers came from Finland and the northern part of Sweden, which suffered from famine.

During the occupation of Norway by Nazi Germany, Vadsø suffered several air raids from the Soviet Union, which bombed German troops.

The municipal council (Kommunestyre) of Vadsø is made up of 21 representatives that are elected to four year terms.

The Varangerfjorden lies along the southern coast of the municipality and the river Jakobselva runs along the western border of Vadsø.

[1] Vadsø town has a subarctic climate, with long winters and a cool short summer.

Part of the municipality is upland at the Varanger peninsula with alpine tundra climate above the treeline.

Spring is a relatively dry season, and precipitation is mainly concentrated in late summer and early autumn.