 In 1719 he became a King's Counsel, and in 1726 he was appointed a Puisne Justice of Chester on the Chester circuit, rising to Chief Justice of Chester in 1729.Willes entered Parliament as MP for Launceston in 1722, and subsequently also represented Weymouth and Melcombe Regis and West Looe.In 1734 he was appointed Attorney General, and was knighted in 1736.