He was Conservative Member of Parliament (MP) for Blackburn from 1931 to 1945. Smiles was re-elected in 1935 but stood for Down in Northern Ireland at the 1945 Westminster election, as a Unionist. The two-seat constituency was split in 1950 into North Down and South Down. Smiles won North Down that year and remained its MP until his death in 1953; he lost his life in the sinking of off Larne Lough, in the Great Storm. He was succeeded by his daughter, Patricia Ford. He is the great-grandfather of explorer Bear Grylls.