Seddon will carry out pre-painting repairs and redecoration to 2,500 homes in South London, Crawley, Brighton and Bexley.
The year-long contract was awarded through a competitive tendering process.
Seddon expects to take on up to 60 new staff who will be recruited in areas local to where the work will be carried out.
Seddon Property Services has been providing painting and maintenance services to London & Quadrant for the past seven years.
Lee Painter, strategic operations manager for Seddon Property Services, said: “We’re extremely pleased to be continuing our strong working relationship with London & Quadrant and are delighted that this new contract will also enable us to create jobs in the communities where we will be working.”