The deal has been done through the Government's National Clearing House with Bovis Homes. This is the largest deal so far agreed with a major housebuilder through the Clearing House Programme.
The deal provides 379 affordable homes on sites across the country following the agreement between the Homes and Communities Agency, Bovis Homes, and a number of Housing Associations.
This means that 4,800 homes in total have now been brought into use as affordable housing for a total of £160 million, with more deals in the pipeline.
Housing minister Margaret Beckett said: "We are determined to support house builders to weather the current difficult climate."
Homes and Communities Agency chief executive Sir Bob Kerslake said: "By being flexible with our funding we have secured more much-needed quality new homes - for affordable rent or sale to local people priced out of the market - and maximised value for public money. And while I am pleased with this early success for the HCA, there is much more to be done as we seek to stimulate development and help maintain the housebuilding industry's capacity through difficult economic conditions."