Sir William Alington, Knt. (died 1446), lord of the manor of both Bottisham and Horseheath, Cambridgeshire, was Speaker of the House of Commons of England, Treasurer of The Exchequer, and High Sheriff of Cambridgeshire and Huntingdonshire.
Sir William Alington married Joanna, daughter of Sir William Burghe, Knight Banneret, Lord Chief-Justice of the King's Bench.
He was appointed High Sheriff of Cambridgeshire and Huntingdonshire in 1414 and 1423. He was elected to Parliament in 1410, 1416 and 1429 as Knight of the Shire for Cambridgeshire and elected Speaker of the House in 1430. He was Privy Councillor to Henry IV and Henry V.
Alington's two sons, Sir William (died 5 July 1459), of Horseheath, and Robert, of Bottisham, both married daughters of the famous Sir John Argentyne, Knt.,of Great Wymondley Manor, Hertfordshire, by his wife Margaret Calthorpe (1380–1427). By this marriage, Sir William junior acquired the manor of Wymondley, which was held in Grand Sergeanty by the service of presenting the first cup at the Coronation of Kings of England; which service was performed by the Lords of that Manor into the 20th century.