The Rt. Hon. Thomas Lough, P.C. (1850 – 11 January 1922), was a British Liberal politician. He was born in Cavan, Ireland to Mathew Lough and Martha Steel, and was educated at the Royal School Cavan and at Wesleyan Connexional School, Dublin. He worked as a tea merchant in London from 1880. He was an unsuccessful Liberal candidate for Truro at the 1886 general election and in 1888 appointed Ramsay MacDonald as a private secretary. Lough was Liberal Member of Parliament (MP) for Islington West from 1892 until 1918. He was Parliamentary Secretary to the Board of Education from 1905 until 1908