Leveling seat

Leveling seats (Danish. Tillægsmandat, Swedish. Utjämningsmandat, Norwegian. Utjevningsmandater, Icelandic. Jöfnunarsæti, German. Ausgleichsmandat), commonly known also as adjustment seats, are an election mechanism employed for many years by all Scandinavian countries and Iceland in elections for their national legislatures. They are the seats of additional members elected to supplement the members directly elected by each constituency. The purpose of these additional seats is to ensure that each party's share of the total seats is roughly proportional to the parties' overall shares of votes at the national level. Relatively recently, Germany has also introduced national leveling seats for the lower house of their national parliament (the Bundestag).

In 1915, Denmark became one of the first countries in the world to introduce leveling seats in their parliamentary elections. Since then, all parliamentary elections in Denmark have allocated these adjustment seats as a substantial fraction of the seats in the parliament. The parliamentary seats currently comprise 135 county seats and 40 leveling seats, with a further 4 "North Atlantic seats" elected separately by proportional representation in the Faroe Islands and Greenland (which are not treated as an integral part of the Danish election system). The leveling seats are supplementary to the normal seats which are allocated by proportional votes within each county. All parties which achieve at least 2% of the national votes are granted as many leveling seats as required to achieve proportional representation at the national level.

Leveling seats have been a part of the election procedures for all Icelandic parliamentary elections since 1934.

Since 1970, Sweden used leveling seats in its elections for both the Parliament and County Councils, for parties having qualified with a total share of votes above a 4%-limit in parliamentary elections and 3%-limit in county council elections. Sweden did not use leveling seats for elections to its Municipalities before 2018. With the new election law (effective from the election 2018), leveling seats are used in municipalities with more than one electoral district.

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