A by-election for the Trutnov Senate seat in the Czech Republic was held over two rounds in January 2018. The first round was held on 5 and 6 January 2018, with the second round on 12 and 13 January. The front-runners in the election were Jan Sobotka, supported by right-wing parties, and Jiří Hlavatý, the candidate of ANO 2011. Both of these candidates qualified for the second round held on 12 and 13 January 2018, which was won by Sobotka with 67% of votes.