Vestfold is one of the 19 multi-member constituencies of the Storting, the national legislature of Norway. The constituency was established in 1921 following the introduction of proportional representation for elections to the Storting. It consists of the municipalities of Færder, Holmestrand, Horten, Larvik, Sandefjord and Tønsberg in the county of Vestfold og Telemark. The constituency currently elects six of the 169 members of the Storting using the open party-list proportional representation electoral system. At the 2021 parliamentary election it had 182,961 registered electors.