The masterplan is to include an Urban Design brief and conservation area assessment, together with a study of infrastructure, heritage and sustainability issues.
Bath is a UNESCO World Heritage site and the council hopes to use the project as "an international exemplar of sustainable urban renewal". The proposed development will be linked to a park-and-ride scheme at Newbridge, on the edge of Bath city centre.
The London Development Agency, Transport for London and the London Borough of Lewisham are representing the public sector.
In the invitation to tender, they said: "The selected development partner will be expected to prepare a masterplan for the entire site and to seek detailed planning consent."