Thomas Jones (ca. 1550 – 10 April 1619) was Archbishop of Dublin and Lord Chancellor of Ireland. He was also Dean of St. Patrick's Cathedral and Bishop of Meath and the patrilineal ancestor of the Viscounts Ranelagh.
Jones was a native of Lancashire and the son of Henry Jones, Esq. of Middleton. His brother, Sir Roger Jones, Alderman of London, was knighted at Whitehall. Thomas acquired a Master of Arts from Christ's College, Cambridge in 1573, after which he relocated to Ireland. He married a widow, Margaret Purdon, who was also a sister-in-law of Archbishop Adam Loftus. The relationship to Loftus proved beneficial to Jones. He has been referred to, uncharitably, as Loftus's "pale shadow"; a more balanced view is that the two men thought alike and worked harmoniously together.
He was named Chancellor of St. Patrick's Cathedral and was elected Dean in 1581. While Dean, Jones granted questionable leases of church property including a particular 161-year lease of a coal mine which caused a later St. Patrick's Dean, Jonathan Swift, to rebuke Jones severely for his improvidence:
A lease of Colemine (i.e. a coal mine) made by that rascal Dean Jones, and the knaves or fools of his Chapter, to one John Allen, for eighty-one years, to commence at the expiration of a lease for eighty-one years, made in 1585; so that there was a lease for 161 years of 253 acres (1.0 km2), within three miles (5 km) of Dublin, for 2l. per annum, now worth, 150l.