Stanmore station was opened on December 10, 1932, as the terminus of the eponymous branch of the Metropolitan Line. This branch was transferred to the Bakerloo Line in 1939 and again to the Jubilee Line in 1979.
The station is on the south side of London Road, part of the A410. There is a traffic light controlled pedestrian crossing across London Road. Between that road and the station, there is a service road used by buses stopping at the station.
In 1934, a proposal to extend the Metropolitan line onwards to Elstree station on the Northern Heights plan was discussed by the LPTBs Engineering Committee; this would allow Metropolitan trains to stable at the proposed Aldenham depot. It would have required 1.2 miles of double track tunnel; Stanmore station being constructed with possible further extension in mind.
Unusually for an above ground station, the ticket office is not in the entrance hall but downstairs at platform level, although a large bay area now containing rarely used public telephones once held the booking hall. The station building also incorporates a number of retail units. Just to the right of the entrance is a minicab office, and to the right of that is a newsagent. To the left is a traditional barber's shop.
In 2005, Transport for London began the construction of a third platform at the station. While this was structurally complete as of summer 2009 it will not be opened until new signalling equipment on that part of the line is brought into use, work which is scheduled for late 2010.
From 1890 until 1952 Stanmore was also served by a branch line (built by the LNWR) from Harrow and Wealdstone, with one intermediate station at Belmont, opened in 1932 (possibly as a counter to the opening of the Metropolitan branch line). This Stanmore station was entirely separate from the Underground station of the same name. It located on the south side of the junction of Gordon Avenue and Old Church Lane; the station was later known as "Stanmore Village" to avoid confusion with the Underground station. Stanmore Village station was closed by British Railways in 1952, with Belmont going the same way in 1964.