Continuity mistake: In the scene where the Chamber finally opens, we first see Harry, Ron and Professor Lockhart from the front, and Harry and Ron are slightly behind Lockhart, and in a position to threaten and guard him. When you next see them a moment later from behind, Lockhart is behind them and they are in no position to guard him. (01:58:45)
Continuity mistake: In the breakfast scene at the Weasleys' house, when Mrs Weasley tells her husband about his sons flying to Harry's house to rescue him, he has something on his fork. Then he asks Harry about rubber ducks, and he cuts up something else. But when he finishes, the only thing on his fork is the original item. (00:13:00)
Continuity mistake: When Harry and Ron are talking to Myrtle when she said somebody threw a book at her she turns around and starts crying. If you look when she starts crying her face is all screwed up. When the camera angle changes when she stops turning and walks off, her face is no longer screwed up. (01:27:00)
Continuity mistake: After being tossed out of the car, Ron and Harry chase after it when it drives off. In the wide shots, as they run through the outside corridor and when they stop at the arched doorway, their breath is visible in the air around them. Whereas their breath is not visible in the previous or following shots. (00:28:30)
Other mistake: When Harry is talking to Dobby in his bedroom on Privet Drive, Dobby begins banging his head against the dresser to punish himself. If you look closely, you can see that there is a slight delay between the time that Dobby's computer-animated head appears to hit the dresser, the time you hear the thump, and the time when the drawer moves and the dresser shudders. (00:04:10)
Revealing mistake: In Harry's bedroom, when Harry and Dobby grapple with the lamp, just as Harry says, "Give me the lamp!" Dobby's left hand is between both of Harry's hands gripping the lamp stem, but in the reflection we do not see Dobby's hand, or arm, as he moves about on the desk, nor do we see the fingers of his right hand which grips the base. In this shot what we do see in the reflection are Harry, his hands, the lamp base, stem, shade and cord. No Dobby. (00:05:30)
Continuity mistake: When the car lands in front of the Burrow, it touches the ground just in front of a small shed and passes it within seconds. An angle change then shows the car driving past the same shed. (00:10:40)
Continuity mistake: In the scene where Harry puts the sword through the head of the snake you can see that only about half a foot of the sword is covered with blood. Then later in Dumbledore's office, when he asks Harry to take a closer look at the sword, you can see that there is blood over almost the entire sword. (02:13:50 - 02:20:50)
Other mistake: Dutch DVD Only: After the duel Harry tells he told the snake to keep away from Justin. In the subtitles, Justin's name appears untranslated. Later when Justin falls prey to the Basilisk he is called by name again but this time his name is translated to Dutch in the subtitles, namely "Joost".
Revealing mistake: While in the Whomping Willow, there is a shot from the interior of the car showing the windshield receiving two large cracks. In the next exterior shot, as the camera pans out while the boys scream, the blue hood of car is seen (with the lack of wiper blades) and the windshield has NO damage whatsoever, as well as when the tree limb comes through the back window, in the two front shots the blue hood is seen and the windshield is intact again. (00:27:15)
Visible crew/equipment: In the Dueling Club scene, as Snape says "Don't move, Potter, I'll get rid of it for you" and walks towards the camera, a film crew chair can be seen on the left side of the screen.