He was the son of Rt. Hon. John Hely-Hutchinson and Christiana Hely-Hutchinson, 1st Baroness Donoughmore. In 1776, he stood as Member of Parliament in the Irish House of Commons for two different constituencies. He sat for Dublin University to 1778 and Sligo Borough to 1783. Subsequently, he represented Taghmon, County Wexford, from 1783 until 1788, when he succeeded to his mother's title. In 1789, he was elected Grandmaster of the Grand Lodge of Ireland, a post he held until 1813.^[1]

He commissioned the building c.1790 of the Georgian style Knocklofty House near Clonmel in County Tipperary. He was created Viscount Donoughmore, of Knocklofty, Co. Tipperary (Peerage of Ireland), on 20 November 1797, with a special remainder to his mother's male descendants and, in 1800, Earl of Donoughmore. He was one of the original 28 Irish Representative peers and an advocate of Roman Catholic emancipation. He was created, in 1821, Viscount Hutchinson (in the Peerage of the United Kingdom) and thus gained an hereditary seat in the House of Lords.^{[citation needed]}

He held the office of Governor of Tipperary and of Lord Treasurer's Remembrancer Court of Exchequer (Ireland). He gained the rank of Lieutenant-General.^{[citation needed]}

• Hansard 1803–2005: contributions in Parliament by the Earl of Donoughmore