Go-Ahead has guaranteed Citybus drivers' jobs for 12 months
The controversial sale of a council-owned bus firm to a private company in Devon has been approved.
A £20.2m bid by Go-Ahead for Plymouth Citybus was agreed at a meeting of the city council.
A group of campaigners gathered outside waved placards and shouted "shame" as councillors went into the meeting.
The Unite union fears the sell-off will lead to job losses and a reduction in routes, but the council said the money from the sale would go into services.
The Conservative-controlled council said it was not equipped to run a bus service.
Go-Ahead has promised to keep the same routes for six months and protect bus drivers' jobs for 12 months.
During the three-hour meeting, Labour leader Councillor Tudor Evans said the council was underselling Citybus and told the meeting it was a "terrible deal for council tax payers".
"It's an appalling deal that robs taxpayers of a valuable resource and puts pressure on already overstretched budgets," Mr Evans said.
But council leader Vivien Pengelly said it was a good decision which would benefit the city and improve local bus services.
"I am very pleased that councillors have made the right decision based on what will be best for people living in the city and public transport users," she said.
"This was a tough decision to make and I'm proud that this city's politicians are mature and responsible enough, in the most part, to set aside our political agendas to ensure that we put the lives of Plymouth people first and foremost in the choices we make."
The sale of Citybus, which will retain its name, will be completed on Tuesday with a formal handover and signing of the sale agreement.