More than 300 jobs are expected to go at Bath and North East Somerset (Banes) Council over the next three to four years.
The council said the slashing of jobs was due to government funding cuts for local authorities.
There will also be a 40% reduction in office space over the next three years.
A Banes spokeswoman said the council would be able to give a more accurate picture of cuts following the government's autumn spending review.
She said: "The 'in year' cuts are just the beginning and are less than a tenth of the total level of cuts that can be expected in the public sector over the next four years.
"The council's approach will be to make savings whilst minimising the impact on front line services.
"However, tough decisions will have to be made and we expect to have to make 300 or more job losses over the next three to four years."