Keston is a village in Greater London, England, located within the London Borough of Bromley, Greater London. Prior to 1965 it was within the historic county of Kent. It is part suburban, part rural in nature and lies on the edge of Hayes Common, just beyond the London conurbation to the south of Bromley Common. It includes the small hamlet of Nash to the southwest. The northern, more suburban part of Keston is sometimes referred to as Keston Mark.

The London Borough of Bromley is a borough in London, England. It borders the county of Kent, of which it formed part of until 1965. The borough's population in the 2021 census was 329,991. It is named after Bromley, its principal district. Other districts are Penge, Hayes, West Wickham, Chislehurst, Beckenham and Orpington. The local authority is Bromley London Borough Council.