Sidcup is an area of south-east London, England, primarily in the London Borough of Bexley. It is 11.3 miles south-east of Charing Cross, bordering the London Boroughs of Bromley and Greenwich, and is in the historic county of Kent.
The name is thought to be derived from Cetecopp meaning "seat shaped or flat topped hill"; it had its earliest recorded use in 1254. The population of Sidcup, including its neighbourhoods Foots Cray, North Cray, Albany Park, Longlands, Ruxley, Blackfen and Lamorbey, was 43,109 in 2011.