Heathrow Airport is located to the west of London surrounded by the communities of Longford, Harmondsworth, Sipson, Harlington, Cranford Cross, Cranford, Hatton, Heston Hounslow, Feltham North, Bedfont, Stanwell, Stanwell Moor, Poyle, Colnbrook, Iver and Richings Park; Brands Hill and West Drayton bordering its perimeter or within close proximity to the airport.

It is bounded to the north by the A4, to the west by the A3044, to the east by the A30 and to the south by the southern perimeter road, the Duke of Northumberland's River and Longford River. The M25 is within 600m of its western perimeter.

It sits within two main river catchments, the River Colne to the west and the River Crane to the east, and is bounded by a number of associated watercourses to the west. A number of reservoirs are located to the west and south west of the area including the Queen Mother, Wraysbury, King George VI, Staines North and Staines South reservoirs. Some of these reservoirs together with other lakes and flooded gravel pits are included in the South West London Waterbodies Special Protection Area (SPA) and Ramsar site which is an international designation for the protection of certain wintering wildfowl.

It currently comprises two runways, four terminals and a network of taxiways and stands, along with ancillary facilities to support its operation and maintenance such as cargo storage, and other airport related development such as hotels, offices and warehouses.