When Alfie speaks with Siddie in the final scene, the ambient light level varies between twilight and dark night.
In Alfie's final monologue to camera, the backdrop changes between cuts, from a view of the South Bank/Royal Festival Hall indicating Alfie is on the North Bank, to a view of the Houses of Parliament that would be visible from the South Bank only.
When Harry Clamacraft eats a banana he holds it in his left hand, but in one shot, as he coughs, it disappears and then immediately reappears again.
When the lorry stops to pick up Annie, Alfie, in the Rolls, follows it in to the lay-by. But the next shot shows the Rolls has stopped short of the lay-by and is still on the main road.
When Alfie arrives in Ruby's apartment, he pulls his tie loose, which pops the button on his shirt collar undone. A few moments later, when Alfie takes a drink, the button is done up again.
Alfie's seduction of Lilly takes place in midsummer. The next time we see her we are told that three months have elapsed, but the foliage still shows it to be midsummer.
When Alfie encounters the church where he sees Malcolm, the church bell chimes the top of the hour. But the clock in the steeple shows not quite half past the hour.
When Alfie is in the doctor's office and looks out of the window at the funeral, the window frame is of a different sort to the one we see of the interior.
Fly-wire visible on the guy who is thrown through the paneling at the end of the pub fight.
We see a street sign showing that Alfie's flat is in Chepstow Road, W3. Later in the film, he goes for a walk with his neighbor leaving Lilly in the flat. They are seen walking in the area behind King's Cross station, several miles from W3.