Although originally scheduled to take place on the same day, the election in the Bodmin St Petroc ward was countermanded following the death of Liberal Democrat candidate Steve Rogerson and was held on 8 June.

These were abolished as part of the 2009 structural changes to local government in England, which created a singular unitary authority.

[3] The previous two elections resulted in no group gaining a majority, requiring the support of independents for any single party to govern.

[7] The electoral division results listed below[10] are based on the changes from the 2013 elections,[11] not taking into account any mid-term by-elections or party defections.

[2] The May 2017 election in the Bodmin St Petroc ward was delayed following the death of Liberal Democrat candidate Steve Rogerson and was held on 8 June, remaining vacant in the interim.

[17] Grenville and Stratton councillor, Paula Dolphin, resigned from the Liberal Democrats on 20 February 2018, continuing to sit as a standalone Independent.

All three councillors had been a part of the Council's ruling coalition – Tudor resigned from the Liberal Democrats and Egerton and Wallis from the larger Independent group.