Jones Parry contested Horsham at the general election of 1806 on the 11th Duke of Norfolk’s interest: a double return being made, his election was upheld by the House in January 1807. He again contested the seat successfully at the subsequent general election, but was unseated on petition. He supported the Grenville ministry in office and served on the Maldon election committee in January 1807. In the next Parliament he voted with the minority against the address, 26 June 1807; for the censure motion of 6 July; against the Irish arms bill, 7 Aug.; for Sheridan’s Irish motion, 13 Aug., and in the minority on the Copenhagen expedition, 8 Feb. 1808.
Jones Parry did not seek re-election in this period. During the war of 1812-14 he served on the Canadian frontier. He died 23 Jan. 1853.1Fortescue mss, Norfolk to Grenville, 4 Nov. 1806.