William Illingworth was born in Yorkshire, England on 1 June 1875 and was articled to John Waugh in Bradford, Yorkshire from 1894 to 1897. He then worked as an assistant to Preston & Johnson in 1897-98, and in Bradford City Architects' Office from 1898 to 1902 when he set up his own practice as an architect and surveyor in Bradford. He was Surveyor to the Halifax Suitable Benefit Building Society and the Equitable Bank, Ltd. Illingworth became known for the cinemas and picture houses he built in the North of England between the 1900s and the late 1930s
He was elected a Licentiate of the Royal Institute of British Architects (LRIBA) in 1912 and was admitted a Fellow of the Royal Institute of British Architects (FRIBA) in 1925. He was also a member of Bradford Society of Architects and Surveyors and its President in 1922 and 1935
His address was given as 9 Market Street, Bradford and 13 Fairfield Road, Shipley, Yorkshire in 1912; and 15 Sunbridge Road, Bradford in 1914 and 1939. He died in Bradford, Yorkshire in 1955.
Prince's Hall Picture House, Shipley, Yorkshire, 1911; The Oak Lane Picture House , Bradford, 1912; Dockfield Mills, Shipley, 1914; Peace Mills, Bradford, 1920; Saltaire Picture House, 1922; Gaumont Shipley, Shipley, Yorkshire, 1922; the New church, Frizinghall, Bradford, 1923; Shuttleworth Hall Housing Scheme, 1924; New Victoria Theatre, Bradford, 1930; Dominion Cinema, Leeds, 1934; Odeon Cinema, Bradford; Regal Cinema, West Hartlepool, 1936; Essoldo Hartlepool, Hartlepool, Yorkshire, 1936; Savoy Cinema, Stanningley, Leeds, 1937; and Clifton Cinema, Bramley, Leeds, 1939.
Directory of British Architects 1834-1914. Compiled by Antonia Brodie, et al. Volume 1: A-K. London; New York: British Architectural Library, Royal Institute of British Architects/Continuum, 2001