 He was the son of Sir David Kinloch, 5th baronet of Gilmerton (1710–1795) (son of Sir Francis Kinloch, 3rd Baronet) and his wife Harriet Cockburn (d. 1757) daughter of Sir Archibald Cockburn, an advocate.His year of birth is unclear, but as the younger brother of Sir Francis Kinloch (b.1747) is presumed to be around 1749.