 A by-election was held in Wey Valley ward on 20 October 2016 following the resignation of Cory Russell (Conservative) who won the seat in May 2014.Conservative councillor Claudia Moore (Weymouth West) joined the Green Party in December 2016.A by-election was held in Westham East ward on 4 May 2017 following the resignation of Liberal Democrat councillor Sally Maslin in March 2017.