Biberach (Landtag electoral district)

The constituency includes the municipalities of Achstetten, Alleshausen, Allmannsweiler, Altheim, Attenweiler, Bad Buchau, Bad Schussenried, Betzenweiler, Biberach an der Riß, Burgrieden, Dürmentingen, Dürnau, Eberhardzell, Erlenmoos, Ertingen, Gutenzell-Hürbel, Hochdorf, Ingoldingen, Kanzach, Langenenslingen, Laupheim, Maselheim, Mietingen, Mittelbiberach, Moosburg, Ochsenhausen, Oggelshausen, Riedlingen, Schemmerhofen, Schwendi, Seekirch, Steinhausen an der Rottum, Tiefenbach, Ummendorf, Unlingen, Uttenweiler, Wain, and Warthausen within the district of Biberach.^[2]

There were 134,636 eligible voters in 2026.

Both prior to and since the electoral reforms for the 2026 election, the winner of the plurality of the vote (first-past-the-post) in every constituency won the first mandate.

Prior to the electoral reforms for the 2026 election, the seats in the state parliament were allocated proportionately amongst parties which received more than 5% of valid votes across the state. The seats that were won proportionally for parties that did not win as many first mandates as seats they were entitled to, were allocated to their candidates which received the highest proportion of the vote in their respective constituencies. This meant that following some elections, a constituency would have one or more members elected under a second mandate.

Prior to 2011, these second mandates were allocated to the party candidates who got the greatest number of votes, whilst from 2011-2021, these were allocated according to percentage share of the vote.

As the CDU won overhang seats in 1976, 1980, and 1984 within the Tübingen administrative district, this constituency returned members for both the first mandates and second mandates - the later of which were awarded to the substitute candidates.