Homeless charity Shelter and property developer Crest Nicholson have formed a three-year partnership.
Crest Nicholson will pay for the charity to employ an extra person on its Shelterline phone service for one year. This will allow a further 2,300 calls to be answered.
Chris Holmes, director of Shelter, said: "It's fantastic to know that the whole company and its customers are supporting Shelter and the work we do with homeless and badly housed people."
Crest Nicholson will also work on Shelter's project to create a welcoming home for a recently re-housed family.