 Route 45 was introduced on 1 October 1950 as a replacement for trolleybus route 34 between Battersea and Farringdon Street via Clapham Junction, Clapham Common, Stockwell, Brixton, Camberwell Green, Elephant & Castle and Blackfriars Bridge.It was operated by AEC Routemasters.On 17 January 1951 it was extended from Battersea to South Kensington station.