A by-election was held in Grendon Underwood and Brill on 23 December 2015 after the death of Conservative councillor and former leader of the council John Cartwright.[4] The seat was held for the Conservatives by Cameron Branston with a majority of 51 votes over Liberal Democrat Julian Newman.[4]
Grendon Underwood and Brill by-election 23 December 2015[4][5]
A by-election was held in Elmhurst on 6 April 2017 after the resignation of UK Independence Party councillor Andy Hetherington.[6][7] The seat was won for the Liberal Democrats by Susan Morgan with a majority of 634 seats over Labour's Gary Andrew Paxton.[8]
A by-election was held in Central & Walton on 22 March 2018 following the resignation in February of Conservative councillor Edward Sims.[12] The Liberal Democrats' Waheed Raja gained the seat.[13]
Quainton
A by-election is expected in Quainton following the death of Kevin Hewson (Conservative) in February 2018.[14]
Changes in affiliation
Tom Hunter-Watts left the Conservative Party and on 5 May 2017 joined the Lib Dems.[15]
On 9 May 2017, all three of UKIP's remaining councillors left the party.[15]