Barnsley is a market town in South Yorkshire, England. It is the main settlement of the Metropolitan Borough of Barnsley and the fourth largest settlement in South Yorkshire. The town's population was 96,888 in 2021, while the wider borough had a population of 244,600 in the 2021 census.

A market town is a settlement most common in Europe that obtained by custom or royal charter, in the Middle Ages, a market right, which allowed it to host a regular market; this distinguished it from a village or city. In Britain, small rural towns with a hinterland of villages are still commonly called market towns, as sometimes reflected in their names.