In the past many routes have changed operator.

This whole section is dedicated to routes that have been with past operators and also operators that are no longer with us.
Abellio London: 2009 - PresentArmchair: 1990 - 2005Arriva (Cowie Group)Atlas BusBexleybusBorolineBTSCapital Citybus: 1990 - 1998Centra London: 2004 - 2005Citarama: 1987 - 1989Connex Bus: 2000 - 2004Crystals: 1985 - 2003Ealing Community Transport: 2003 - 2009East London (ELBG): 2006 - 2010East Thames Buses: 1999 - 2009Ensignbus: 1989-1990 & 1999Epsom Buses (Quality Line): 1980 - PresentFirst: 1997 - 2013Go Ahead London: 2008 - PresentHarris Bus: 1997 - 2000Harrow BusesLeaside BusesLimebourne: 1996 - 2001London BuslinesLondon Country (London & Country)London Easylink: 2000 - 2002London LinksLondon Traveller: 1988 - 2001London United (RATP Group)Luton & DistrictMetroline (Comfort Delgro): 1988 - PresentMitcham Belle: 1999 - 2004NSL Services (NCP Challenger): 2005 - 2009R & I BusesSelkent (ELBG): 2006 - 2010Stagecoach London: 1994 - 2006Stagecoach London: 2010 - PresentTellings Golden Miller: 1999 - 2005Thameside (ELBG): 2009 - 2010ThameswayThorpes: 1998 - 2007TranscityTransdev (London United & London Sovereign)Travel London: 2004 - 2009Westlink