After the war, Sykes was appointed the Controller of Civil Aviation and he continued in this role until 1922 when he entered politics, becoming the Conservative MP for Sheffield Hallam, which he held until 1928 when he resigned. From 1928 to 1931 Sykes was Governor of Bombay, after which time he returned to Great Britain where he involved himself in business and public life. During the Second World War, Sykes was an MP once more, this time for Central Nottingham. He lost his seat in 1945 and he died nine years later.