The London Borough of Hillingdon is the largest and westernmost borough in West London, England. It was formed in 1965 from the districts of Hayes and Harlington, Ruislip-Northwood, Uxbridge, and Yiewsley and West Drayton in the ceremonial county of Middlesex. Today, Hillingdon is home to Heathrow Airport and Brunel University, and is the second largest of the 32 London boroughs by area.

West London is the western part of London, England, north of the River Thames, west of the City of London, and extending to the Greater London boundary.