Sir William Lowther (18 August 1639 – 7 December 1705) was an English landowner and MP.
He was the eldest son of Sir William Lowther of Swillington, near Leeds and educated at Gray's Inn and Balliol College, Oxford.
He was commissioner for the Aire and Calder Navigation in 1699 and elected Member of Parliament for Pontefract in 1695, sitting until 1698.
He had married Catherine, the daughter of Thomas Harrison of Middlesex, and had ten children,[1][2] the eldest being Sir William Lowther, 1st Baronet.
He had a falling-out with his eldest son, William, over his marriage to the daughter of Lord Maynard, because of the reduction in the estates that would be entailed by her jointure.