He adopted the surname Conolly by Royal Licence on 27 August 1821, following the death of his great-aunt Lady Louisa Conolly.
He lived at Castletown House in County Kildare, which he inherited from his great-aunt Louisa, and 'Cliff House' in County Donegal. He represented Donegal in Parliament from the general election in 1831 until his death, and was a lieutenant-colonel in the Donegal Militia. The Conolly residence 'Cliff House' on the banks of the River Erne between Belleek, County Fermanagh and Ballyshannon, County Donegal was demolished as part of the Erne Hydroelectric scheme, which constructed the Cliff and Cathaleen's Fall hydroelectric power stations. Cliff hydroelectric power station was constructed on the site of 'Cliff House' and was commissioned in 1950.