Longcross was a British construction company which entered into administration in June 2015.The head office was based in Ashtead, Surrey, England. The company undertook a number of projects for the University of Oxford, including at the Clarendon Laboratory, Denys Wilkinson Building, Mathematical Institute, Merton College, Queen Elizabeth House, Osler House, and a number of other departments. In June 2012, the New Radcliffe House on Walton Street, the new location of the Jericho Health Centre, on the Radcliffe Observatory Quarter development site, was completed by Longcross.