Diana Moore has taken the seat off Labour in the St David's ward after Thursday's local elections.
Labour are still in control of the City council, with 29 councillors - the Conservatives lost two seats, the Liberal Democrats have gained one seat and there's one Independent councillor.
There is still no overall control of Torbay Council but the Liberal Democrats and Independent each gained five seats as the Conservative lost nine.
In North Devon, the Liberal Democrats have taken control of the council.
“Disappointment” over North Devon funding settlement
Controversial Exeter road consultation to begin in the New Year
South Hams big bang ban turns into a damp squib
Exeter care agency rated 'inadequate' and in special measures
Raw sewage spews into Plymouth suburb estate and woods
Councillor stands under trees to stop chainsaw massacre
