A state election was held on 15 October 2017 to elect the 18th Landtag of Lower Saxony. The turnout was 63.1%
Following the previous state election in 2013, a red-green coalition between the SPD and Greens was formed, holding a one-seat majority in the Landtag of Lower Saxony. After Green parliamentarian Elke Twesten defected to the CDU on 4 August 2017, the coalition lost its majority, which prompted Prime Minister Stephan Weil to call to schedule an early election for 15 October. The Landtag was officially dissolved on 21 August after 135 of 137 parliamentarians voted in favor, with 91 votes required for its dissolution.
The Landtag of Lower Saxony is elected using a mixed-member proportional representation system with at least 135 seats. Of these, 87 are elected in single-member constituencies, and the remainders are determined by party election lists. As in federal elections, voters have two votes: the first vote for candidates within each individual constituency, and the second vote for party election lists. There is a 5% threshold for the second vote in order to receive representation from party election lists. Seats are allocated using the d'Hondt method, with additional overhang and leveling seats to ensure proportionality of party representation relative to their share of second votes after the initial 135 seats have been allocated. The normal duration of the Landtag is 5 years.
Official preliminary results put the Social Democratic Party (SPD) ahead with 36.9 percent of the vote, followed by the CDU with 33.6. The Greens earned 8.9 percent and the Free Democratic Party (FDP) came in with 7.5 percent.
The far-right populist Alternative for Germany (AfD) could make its way into the state parliament on 6.2 percent. It marks the 14th of Germany's 16 state parliaments where the AfD has won seats.
The Left's 4.6 percent result means that despite increasing its share of the vote by 1.5 percentage points it won't make it over the 5-percent hurdle for parliamentary representation.