Running between Walthamstow bus station and Oxford Circus, it is operated by Stagecoach London.

The route number 55 came from tram 55, replaced by trolleybus 555, which had run between Old Street and Hackney.

[1] In 1990, the section of the route that linked Leyton and Oxford Circus was withdrawn.

[2] On 13 October 2001 conductors were reintroduced on route 55, using standard two door double deckers that were previously one person operated.

The vehicles employed generally had bell pushes that would only ding once reducing the effectiveness of the second crew member.