Carshalton is a town, with a historic village centre, in south London, England, within the London Borough of Sutton. It is situated 9.5 miles (15.3 km) south-southwest of Charing Cross, in the valley of the River Wandle, one of the sources of which is Carshalton Ponds in the middle of the village. Prior to the creation of Greater London in 1965, Carshalton was in the administrative county of Surrey.

The London Borough of Sutton is an Outer London borough in London, England. It covers an area of 43 km2 (17 sq mi) and is the 80th largest local authority in England by population. It borders the London Borough of Croydon to the east, the London Borough of Merton to the north and the Royal Borough of Kingston upon Thames to the north-west; it also borders the Surrey boroughs of Epsom and Ewell to the west and Reigate and Banstead to the south. The local authority is Sutton London Borough Council. Its principal town is Sutton.