gained control of the council from the Liberal Democrats and Plaid Cymru, after gaining 32 seats. The Liberal Democratleader of the council, Rodney Berman, lost his seat by 51 votes after two recounts, bringing Labour's gains to 33. Sixty-one-year-old Labour councillor Heather Joyce, nicknamed 'Supernan' by the local newspaper, became the new council leader.
Manifestos
Cardiff Greens Cardiff Labour Cardiff Liberal Democrats Cardiff Plaid Cymru
Duncan Macdonald had been elected as a Conservative in 2008.
Splott (3 seats)
Trowbridge (3 seats)
Whitchurch and Tongwynlais (4 seats)
By-elections between 2012 and 2017
Riverside
The by-election was caused by the resignation of Labour councillor Phil Hawkins for personal reasons.
Splott
A by-election was caused by the resignation of Labour councillor Luke Holland following accusations of non-attendance at council meetings. He stated that he planned to move to London.
Canton
The by-election was caused by the resignation of Labour Councillor Cerys Furlong on 30 December 2013.
Llandaff North
The by-election was caused by the resignation of Labour councillor Siobhan Corria for personal reasons.
Pentyrch
The by-election was caused by the resignation of Labour Councillor Craig Williams, following his election as MP for Cardiff North.
Riverside
The by-election was caused by the resignation of Labour councillor Cecilia Love for family reasons.
Plasnewydd
The by-election was caused by the death of Labour councillor Mohammed Javed.
Grangetown
The by-election was caused by the death of Labour councillor Chris Lomax.
Defections 2012-17
In April 2013 Gabalfa Councillor Gareth Holden resigned from The Lib Dems to sit as an independent and later joined Plaid Cymru.
In June 2015 Rhiwbina Councillors Jayne Cowan and Adrian Robson both joined the Conservatives.
In January 2016 Trowbridge Councillor Ralph Cook left Labour to sit as an independent. In 2017 he contested his seat for the Lib Dems.
In May 2016 Llanrumny Councillor Derrick Morgan left the Labour group and sat as an independent.
In August 2016 Splott Councillor Gretta Marshell resigned from Labour to sit as an independent and later joined Plaid Cymru
In early 2017 Adamsdown Councillor Manzoor Ahmed was deselected by Labour and joined the Lib Dems.
Three seats were vacant by the end of the term caused by the resignation of Margaret Jones in Cyncoed, the resignation of Susan White in Llandaff North and the death of a Derrick Morgan in Llanrumny, all of happened within six months of the 2017 election, so no by-elections were held.
