The project involves the £33m redevelopment of the existing council offices site in Keynsham on the outskirts of Bristol with new shops, a library and new council offices.
Construction is expected to a start on site in August after designs under the two-stage bidding process have been finalised.
The builder is scheduled to complete the council regeneration project two years later.
The project will allow the council to reduce the amount of office space it uses from 12 building to four and become more financially efficient.
Reduced running costs will deliver 10% annual savings that will benefit the local taxpayer public purse. The Council carbon footprint specifically in its buildings will reduce by up to 70%.