Although the character Stan Butler was supposed to be in his mid-30s, Reg Varney was already 52 when the series began. He wore heavy make-up so that he would appear younger.
There were plans to revive the series in 1990 as "Back on the Buses".
Bob Grant, playing bus conductor Jack, had actually worked in real life as a bus driver in order to pay his way through RADA (the Royal Academy of Dramatic Art). He mentions this in the TV interview he did on the Wogan show in 1990. The rest of the cast were also present talking about the planned new series which sadly never got made.
Reg Varney was the first person in the UK to publicly use a cash point, when he was hired by Barclays Bank to publicize the first ATM available to the public.
Due to a technicians' strike during Season 4, seven of the 13 episodes were made in black and white rather than color--"Christmas Duty", "The Anniversary", "Cover-Up", "Safety First", "The Lodger", "The Injury" and "Not Tonight". On some of these a voice is audible directing the audience's applause prior to the credits cutting off.