A refurbished council centre in part of Lincolnshire should make accessing services easier and save money, officials have said.
The Festival Hall in Caister Road, Market Rasen, has a contact point for West Lindsey District Council.
But work on a new reception, toilet and interview room will see it expand to also offer county council services.
This will give "substantial savings" but will mean the offices closing from 8 November until January.
District council leader and county council member for Market Rasen, councillor Burt Keimach, said: "The project makes sense because people do not always know which council provides which service so if everyone is under the same roof it makes things much easier for the public.
"There will also be substantial savings in running costs which will be particularly welcome in the current financial climate."
During the work district council services will be available from the county council office in King Street, he added.