Cheltenham is a suburb of Sydney, in the state of New South Wales, Australia. Cheltenham is 21 kilometres north-west of the Sydney central business district in the local government area of Hornsby Shire. Cheltenham is considered to be part of the Northern Suburbs.
This residential suburb has a distinctive English atmosphere, with a number of 19th Century mansions on tree-lined streets. Cheltenham shares its postcode of 2119 with Beecroft and has sometimes been viewed as simply part of that suburb. Most residents of Cheltenham see themselves as distinct from Beecroft, although local issues are addressed together in the Beecroft Cheltenham Civic Trust.