Councillors Karina Green and Margaret Forsyth have joined deputy mayor Gordon Chesterman and Mayor Julie Hardaker in their decision not to seek re-election in the upcoming local body elections.
Ms Green said her decision had been based on a need to spend more time with her children and family.
"I've had a lot of things change in the last 12 months so for me family has to be a priority right now. I didn't want to sit in a seat with the amount of responsibility that comes with it."
Ms Green said her main advice to new hopefuls was not to expect much thanks from the public.
"On reflection I am disappointed at how thankless the position of councillor is within the wider community. When I look back and reflect on how much work and time goes into being a councillor, particularly with reading reports and that sort of thing, making a decision is not always an easy process."