Basil Marriott was born in St. Ives, Cornwall, England on 6 October 1902. It is not known where he received his training as an architect. He taught for a period at the Architectural Association Schools in London and then worked as an art director with the Empire Marketing Board. In the late 1930s he was involved in establishing the Reimann School in London. This was the British branch of a commercial art school based in Berlin. Marriott worked as the school's publicity officer until 1940 when it was destroyed by bombing, the same fate which the Reimann School in Berlin.
Between 1943 and 1946 Marriott served in the British Army and from 1944 was attached to the Monuments, Fine Arts, and Archives (MFAA) Subcommission of the Allied Control Commission in Italy and was engaged in the protection and preservation of ancient monuments. He also lectured on art to the British troops.
In 1946 he returned to England and resumed his architectural practice. In 1948 he was elected a Licentiate of the Royal Institute of British Architects (LRIBA). He joined the Royal Commission on Historical Monuments and was responsible for the design of its numerous publications. He also wrote extensively for architecture journals. He died in Lambeth, London on 7 March 1971.