Continuity mistake: Near the end when Kate is in her hall gown, her dress bodice is plain and the skirt comes to her ankles. When she stumbles in to Leopold's party, her bodice now has short black lace and her skirt has a train and a bustle.
Continuity mistake: In the close up shot of Kate holding the photos during her acceptance speech, the hand holding the photos is a man's hand. (01:46:32)
Continuity mistake: In the board meeting scene in which the margarine commercial auditions are first being looked at, the video gets paused on the first man auditioning and then the second man auditioning, but in each subsequent shot of the television, it's back to being paused on the first man auditioning. (00:29:49)
Continuity mistake: When Kate appears in 1876 New York, including at the ball, she is wearing a different gown to the dress she was wearing in modern day New York. (01:51:18 - 01:53:10)
Continuity mistake: At the end when Kate arrives at the uncle's house, Otis says "what seems to be the problem?" The doorman looks up at Otis, but the very next shot is Kate and the doorman is looking at her. (01:51:50)