London Transport purchased 1,440 MkI examples between 1978 and 1985, numbering them M1 to M1440. Two MkII prototypes were delivered to London Transport as M1441 and M1442 in 1984, but there were no further orders. In 1987 and 1988, 14 secondhand Metrobuses were purchased from Greater Manchester PTE, West Yorkshire PTE and Busways. London Transport's low-cost subsidiary Harrow Buses leased 29 new MkII Metrobuses in 1987, but had to return them to their lessor three years later. London Transport's Metrobuses were the mainstay of the double decker fleet between 1987 and privatisation in 1994, when most of them passed to seven of the new operators.
MTL bought the London Northern company, with a host of Metrobuses. It acquired more when it took over London Suburban Buses, and including some ex-London examples from its Merseyside operation. Garages were at North Acton, Holloway and Potters Bar. Metroline Northern perations in London dwindled during 2002, with Ms replaced by low-floor buses on most routes. Some clung through 2003 on as deputising on the AEC Routemaster routes, but operation on TfL services ceased in March 2004. Potters Bar was the last outpost, where a handful remained on other services until May 2005; where the Volvo Olympians took over.
London General reached the end with Metrobuses in normal service in February 2003, when Stockwell's last were withdrawn. This still left a couple for special purposes (M1440 at Sutton and the "spotted cow" liveried M1435). There was still a crowd of white-blouse and grey-skirt training buses too, which were mainly moved out from their comfy homes to the Plough Lane open-air space, to make room for the new larger fleet of low-floor WVLs. There is an open-top MCW Metrobus for use by hire in London General; it was also replaced by the withdrawn NVs that left route 74 with a lurch.