Earl of Kilmarnock was a title created twice in the Peerage of Scotland for the Boyd family. It was first created in 1454 for Robert Boyd, Great Chamberlain of Scotland. It was created a second time in 1661 for . Both titles were forfeited in 1746. Thomas Boyd, the elder son of Robert Boyd, 1st Lord Boyd—and father of the second one—was created Earl of Arran in 1467, but both titles were forfeit in 1469. Considerable confusion exists over the numbering of the Lords Boyd; this article follows the numbering used in the Oxford Dictionary of National Biography.