The 2015 Horsham District Council election took place on 7 May 2015 to elect members of Horsham District Council in England. It was held on the same day as other local elections and the 2015 United Kingdom general election. The Conservatives secured a majority of 17, which was the largest majority any party has ever achieved at a Horsham District Council election.
Prior to the election, the composition of the council was:
After the election, the composition of the council was:
David Sheldon was elected as a Liberal Democrat in Denne ward in 2011, the year when this seat was last up for election, he resigned from the party in 2014.
Independent candidate Nicholas Butler stood as a Liberal Democrat in 2011 in Roffey North.
Former Horsham Football Club manager, Gary Charman, stood as a candidate for the Liberal Democrats in Southwater following the council rejecting the football clubs planning application for a stadium at Hop Oast. The location of the ground falls into the Southwater ward and was opposed by the Conservative councillors representing the ward at the time. A different application at the same location was approved in 2017.