Galston is a parish, which lies in East Ayrshire Council Area, some 7 miles (12 km) east of Kilmarnock and 10 miles (15 km) north 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 61.4 sq. km (23.7 sq. miles) and includes the settlement of Galston. Galston has 6 neighbouring parishes; namely Avondale, Kilmarnock, Loudoun, Mauchline, Riccarton and Sorn. The boundaries of this parish were modified among significant changes recommended by the Boundary Commissioners after the Local Government (Scotland) Act 1889.