South Ruislip is an area of west London in the London Borough of Hillingdon, south-east of Ruislip, south of Eastcote, north-west of Northolt, and west of South Harrow. A 2017 estimation put the population of South Ruislip ward as 13,150 residents.

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.