Windsor House, London is an office building complex in Victoria Street, City of Westminster, which was built in 1973.
The eighteen-storey tower was previously occupied solely by staff from Transport for London but they have since left the building. In January 2018, the Government Property Agency acquired the building. The Homes and Communities Agency took over two floors in March 2018, relocating from the Home Office building at 2 Marsham Street, SW1.
The top four floors are occupied by Department for International Trade as of June 2018.
The Wikipedia page is [1].