Continuity mistake: Before Pollyanna arrives on the train, when Jimmy Bean pushes the metal hoop down the road, two girls stop their doll carriages right beside each other and grab their dolls, but in the next shot their carriages are about 4 feet apart, which is now wide enough for Jimmy to run between. (00:01:10)
Continuity mistake: When Cary Grant tells Deborah Kerr to keep the door closed, she is holding a record album. As a reaction to his directive, she lowers the LP to about waist level. The camera shot changes and she's holding the LP higher again. (00:27:55)
Continuity mistake: Just before Crassus has Spartacus crucified,he tells him the fate of his wife and son. A camera closeup shows a change in Kirk Douglas's hairstyle.
Continuity mistake: In the bar scene, near the beginning of the film, the pint glass that Albert Finney holds, constantly changes position. (00:06:05)
Continuity mistake: In the first elevator scene, when Shirley MacLaine calls the floor number (19), between her, Jack Lemmon and the wall there are a man with a fedora reading the New York Times, and a woman with a turban. When the elevator doors open and people come out of the cabin, the woman is nowhere to be seen. (00:17:05)