Cannon Street station, also known as London Cannon Street, is a central London railway terminus and connected London Underground station in Travelcard zone 1 located on Cannon Street in the City of London and managed by Network Rail. It is one of two London termini of the South Eastern Main Line, the other being Charing Cross, while the Underground station is on the Circle and District lines, between Monument and Mansion House. The station runs services by Southeastern, mostly catering for commuters in southeast London and Kent, with occasional services further into the latter.

The London station group is a group of 18 railway stations served by the National Rail network in central London. The group contains all 14 terminal stations in central London, either serving major national services or local commuter routes, and 4 other through-stations that are considered terminals for ticketing purposes. All current stations in the group fall within London fare zone 1. A ticket marked "London Terminals" allows travel to any station in the group via any permitted route, as determined by the National Routeing Guide.