Central London is the innermost part of London, in England, spanning the City of London and several boroughs. Over time, a number of definitions have been used to define the scope of Central London for statistics, urban planning and local government. Its characteristics are understood to include a high-density built environment, high land values, an elevated daytime population and a concentration of regionally, nationally and internationally significant organisations and facilities.

The City of London, widely referred to simply as the City, is a city, ceremonial county and local government district that contains the ancient centre, and constitutes, along with Canary Wharf, the primary central business district (CBD) of London and one of the leading financial centres of the world. It constituted most of London from its settlement by the Romans in the 1st century AD to the Middle Ages, but the modern area referred to as London has since grown far beyond the City of London boundary. The City is now only a small part of the metropolis of Greater London, though it remains a notable part of central London. The City of London is not one of the London boroughs, a status reserved for the other 32 districts. It is also a separate ceremonial county, being an enclave surrounded by Greater London, and is the smallest ceremonial county in England.