Balfour beat rivals Colas, Ringway and May Gurney to the contract, which is due to start on June 1.
The deal covers highway maintenance, grass cutting, grounds maintenance, litter collection and street lighting as well as dealing with winter weather, drainage and bridges.
Previously this work had been the responsibility of four different organisations, including an in-house team.
Under the new contract all the works will be carried out by Balfour Beatty Living Places, which had previously held only the street lighting contract.
Ian Tyler, CEO of Balfour Beatty said: “We are delighted to be able to build on our existing relationship with Wiltshire Council.
“We have shown once again the breadth of our skills and experience and that we can deliver for local authorities on a wide range of services.”