Foley was the son of Thomas Foley and his wife Hester (née Andrews), and the cousin, namesake and heir of Thomas Foley, 2nd Baron Foley (a title which became extinct on his death in 1766), thus acquiring Witley Court and the extensive Great Witley estate. The Foley family descended from the prominent ironmaster Thomas Foley.
Foley was elected to the House of Commons for Droitwich in 1741, a constituency he represented until 1746 and again from 1754 to 1768, and then sat for Herefordshire between 1768 and 1776. The latter year the title held by his cousin was revived when Foley was raised to the peerage as Baron Foley, of Kidderminster in the County of Worcester.
Lord Foley married the Hon. Grace (d. 1769), daughter of George Granville, 1st Baron Lansdowne, in 1740. They had seven children:
Foley died in November 1777, aged 61. He was succeeded in the barony by his eldest son, Thomas.