|Began service||9 April 2005|
|Night-time||Night Bus N207|
The conversion of route 207 to articulated buses resulted in the route no longer being able to serve Uxbridge, due to tight turns in the town centre, so the route was split into two sections on 9 April 2005 with the western end between Uxbridge station and Acton renumbered 427, running from Acton (AT) garage using Dennis Trident 2s cascaded from route 207.
Transport for London were proposing to build the West London Tram between Shepherd's Bush and Uxbridge, running along Uxbridge Road. The tram would have replaced routes 207, 427 and 607. Transport for London claimed that trams would carry more passengers and be more reliable, but due to the Crossrail project going ahead the plans were scrapped.
Upon being re-tendered, First London commenced a new contract on 10 April 2010, with new Wright Eclipse Gemini 2 bodied Volvo B9TLs. From the same date the route was due to be extended to Acton Town Hall in place of the former Horn Lane terminus, which was eventually put in effect in January 2011.
On 8 April 2017, the route passed to Abellio London operating from Hayes garage. This contract was only for three rather the usual five years to allow Transport for London the option of restructuring services after the Elizabeth line opened. On 11 April 2020, Abellio London commenced a new contract.
In July 2006 seven passengers on the route were attacked and robbed by a group calling themselves the "MDP".
On 22 August 2008, four youths received stab wounds during a brawl on a vehicle on the route near Hayes. The injuries were not life-threatening.
- Aldridge, John (September 2003). "A real test coming for artics". Buses. Ian Allan Publishing (584): 12.
- Bus tender results Route 427 Transport for London 26 September 2003
- Controversial tram plan derailed BBC News 3 August 2007
- Bus tender results Route 427 Transport for London 14 September 2009
- Bus route extension is boot for shoppers Ealing Gazette 19 January 2011
- FirstGroup Announces Sale of Eight London Bus Depots FirstGroup 9 April 2013
- Aberdeen firm FirstGroup sells off depots for £80m BBC News 9 April 2013
- First quits London bus business Archived 7 June 2014 at the Wayback Machine Bus & Coach Professional 9 April 2013
- Stagecoach loses out to Go-Ahead Buses issue 746 May 2017 page 22
- Abellio secures three London bus contracts Coach & Bus Week issue 1407 20 August 2019 page 7
- Tender News Bus Talk issue 60 October 2019 page 20
- Did you see vicious attack on bus? Hillingdon & Uxbridge Times 29 September 2006
- Four stabbed in gang brawl Hillingdon & Uxbridge Times 22 August 2008
Media related to London Buses route 427 at Wikimedia Commons