Mauchline is a parish, which lies in East Ayrshire Council Area, some 5 miles (8 km) south of Galston and 7 miles (11 km) northwest of Cumnock in East Ayrshire.
It is located in the old county of Ayrshire, which disappeared following the Local Government (Scotland) Act 1974.
The parish has an area of 36.2 sq. km (14 sq. miles). Mauchline has 8 neighbouring parishes; namely Auchinleck, Craigie, Galston, Ochiltree, Riccarton, Sorn, Stair and Tarbolton. The boundaries of this parish were modified among significant changes recommended by the Boundary Commissioners after the Local Government (Scotland) Act 1889.