Carshalton was a constituency combining with areas to the south-west, then to the east instead, Carshalton which is a suburb on a long, north–south hillside south of London. The latter form saw it take up an eastern "half" (i.e. one of two divisions) of the London Borough of Sutton. It returned one Member of Parliament (MP) to the House of Commons of the Parliament of the United Kingdom.
It was created for the 1945 general election having been the south-west of "Mitcham" and on shedding Banstead in 1974 it gained what had been the south-east of the Mitcham seat, then was abolished for the 1983 general election, when it was replaced by Carshalton and Wallington, a nearly identical eastern set of 13 wards of its (post-1965) solely related local government area (London Borough).
The constituency was formed entirely from the existing of constituency Mitcham
The wards of Beddington North, Beddington South, Wallington Central, Wallington North, and Wallington South were transferred from the abolished constituency of Mitcham. Banstead was transferred to the constituency of Reigate
The first version of the seat extended south from the town of Carshalton into the North Downs. Following the redistribution in the late 1960's the seat lost the rural areas of the North Downs to the south and gained suburban areas to the north-east.
As to 1945-1965 period: list of parliamentary constituencies in Surrey
{{cite web}}