The GWR/GCR Joint line to High Wycombe carried services from both Paddington and Marylebone. They met at Northolt Junction, situated slightly to the east of the station, from where four tracks ran westwards to Ruislip Gardens and West Ruislip; there the route shrank to two tracks only. Opened in May 1908 and originally known as Northolt Junction, the station became South Ruislip & Northolt Junction from September 1932 and received its present name in July 1942. The station was first served by Central line trains on 21 November 1948 when the Central line extension from London towards Buckinghamshire was completed after being delayed by World War II. The Royal Air Force station, RAF Northolt, is situated in South Ruislip near the A40 and the tube station. Most early RAF airfields were named after the nearest railway station; in this case Northolt Junction.
Not all Chiltern trains stop at all stations. Travellers are recommended to consult a timetable before travelling. Ticket barriers control access to all platforms. The bridge outside which carries the lines over Station Approach is lower than others locally at 11 feet 9 inches (3.58 m) and is often hit by high vehicles. Either side of it false deck beams have been installed so the danger of any impacts causing damage to the bridge itself has been lessened. The station has payphones and a car park.
Connections: National Rail; London Buses route 114 and E7 serve the station.