IT Telemarketing Services has appointed Regional Property Services to manage the 8,600 sq ft Earle House, Altrincham.
RPS previously served as letting agent for Earle House.
The ground floor is let to Staples International Shipping and Apex Computing Services, with IT Telemarketing Services on the first floor.
Cath Kendal, facilities manager of IT Telemarketing Services, said: "As letting agents Regional Property Solutions has performed at an exceptional level on our behalf in very challenging commercial circumstances and we see it as a natural progression of the partnership to assign to them the responsibility for managing Earle House on our behalf."
Charles Murray, managing director of Regional Property Solutions, said: "This appointment is particularly gratifying as we been the letting agents for Earle House for some years and advising on the management in an unofficial capacity."