In April 1989, in preparation for the privatisation of London bus services, London Buses was divided into 11 arm's-length business units based on different garages.
Eight units inherited Routemasters: CentreWest, East London, Leaside, London Central, London General, London Northern, London United and South London.
During this time, following the failure and premature withdrawal of heralded replacement vehicle classes such as the Daimler Fleetlines, the Routemasters that had not yet been disposed of saw their lives extended for use until privatisation.
Where new route tenders called for Routemaster operation, these were leased from London Buses.

Between September and November 1994, all of the business units were sold.
In the new London route tendering process, all but one of the Routemaster-operated routes (139) retained their now privately owned Routemasters for the five-year contract period and further refurbishments resulted.
In April 1989, in preparation for the privatisation of London bus services, London Buses was divided into 11 arm's-length business units based on different garages. Eight units inherited Routemasters: CentreWest, East London, Leaside, London Central, London General, London Northern, London United and South London. During this time, following the failure and premature withdrawal of heralded replacement vehicle classes such as the Daimler Fleetlines, the Routemasters that had not yet been disposed of saw their lives extended for use until privatisation. Where new route tenders called for Routemaster operation, these were leased from London Buses.
Between September and November 1994, all of the business units were sold. In the new London route tendering process, all but one of the Routemaster-operated routes (139) retained their now privately owned Routemasters for the five-year contract period and further refurbishments resulted.
AEC Routemaster