Continuity mistake: Throughout the movie, Meg Ryan's hair changes styles to depict the different eras. But in a montage of her and Billy Crystal, when it looks like she is doing yet another of her long winded menu requests to an exasperated waiter, he hair is straight and almost waist length. This is her hair style at the very end of the movie, when she and Billy are telling about their wedding cake with the coconut and rich chocolate sauce.
Continuity mistake: During the dinner scene in the restaurant, Marie puts down her glass of cola on the table. In the next shot, she is drinking from the glass again.
Continuity mistake: When Harry and Sally are walking to the museum, telling their stories about their sex dreams, Sally does not have a brooch anywhere on her blazer. However, when they are in the museum, she suddenly has a round brooch on the left lapel of her jacket.
Continuity mistake: When Sally is faking her orgasm, the slice of meat on her sandwich changes the way it's folded over the bun between angles.
Continuity mistake: In the first deli on the way to New York, Sally slides the menu over the table and places it aligned with the border, very close to her. When the angle changes, it is skewed and several inches away and she is bringing it close again.
