Character mistake: In the beginning of the film, Oliver has been brought by Mr. and Mrs. Bumble to the Governor's door after asking for more to eat. Mrs. Bumble then sings, "They'll lay the blame on the one who named him," and as Mr. Bumble is responding, "O-li-ver", look at Oliver. He is completely spacing out and not in character at all - staring off into the distance and flicking his tongue in and out of his mouth.
Deliberate mistake: When Fagin shakes Oliver's hand (when he first meets him) there is a blonde haired boy standing right behind Oliver, but in the shots from behind him, the boy is gone. This may be because the camera is just behind where the boy was and he had to move so they could get the shots from this angle.
Continuity mistake: When Oliver first meets Fagin, he says " aren't we, my dears?" Dodger replies "'course we are Fagin" Dodger then looks up at Fagin and stops smiling. But when the camera zooms in, he does the same thing again, you can tell by his expression that it is the same shot but from a different angle.
Continuity mistake: Just before "Be back soon", Dodgers asks Fagin if Oliver can go out with him and Charlie, earlier we see that Charlie is a small boy with dark hair and a black bakerboy hat. This same boy tells Dodger and Oliver to hurry up at the very end of "Be back soon". But when they arrive in London, Charlie is now someone different. He has a different shaped face and a different outfit. You see this boy earlier, claiming the sausages are mouldy, but there he has blonde hair.
Revealing mistake: When we first see Oliver Reed, we see his shadow first on the wall at a ramp to the pub. As his shadow spreads its legs, we then see him spreading his legs a moment later. Shadow puppetry was used by the director to give the audience the impression that he is ominous and foreboding before we ever see the man himself.
Continuity mistake: During the song "I'd Do Anything" Bet's hair is down and then pulled back, then down again at different parts of the song and dance in that scene.
Continuity mistake: During 'It's A Fine Life', Nancy fills a bowl of soup to give to Bill. Just after she fills it, she puts her arm round Bet's shoulder and Bet puts hers round Nancy's waist. Bet is holding a bowl in her left hand. When it cuts, to show them from the front, Bet is now holding the bowl in her right hand and the other is holding her skirt.
Continuity mistake: During the 'who will buy' scene, the window cleaners come into shot and pitch their ladders to the balcony. The cleaners are beating the carpets over the balcony, and in the same shot you can see the ladders are not attached to the balcony. When the window cleaners climb the ladders and dismount, at the top you can see the ladders are now attached to the balcony with brackets.