Galliford Try Partnerships has signed a development agreement with Ealing Council in London for new council offices and 470 homes.
The proposed mixed-use development at Perceval House, worth an estimated £275m, includes 50% affordable homes, with more than half of these homes provided at social rent and London living rent.
As well as a new council headquarters building, the scheme includes a library and customer services centre and shops.
Galliford Try Partnerships and the Council will now consult the local community before a planning application is submitted later this year.
The new civic centre comes will be paid for from receipts from the sale of the land and homes.
Councillor Julian Bell, leader of Ealing Council, said: “These plans will deliver much needed genuinely affordable homes in our town centre, supporting our pledge of 2,500 new homes.
“At no cost to the council, it will also provide us with a brand-new customer service centre and library, and a smaller, more modern and cheaper to maintain and run office block.”
It is anticipated that the scheme will be completed by 2025, subject to planning consent.