Continuity mistake: When trying to catch Neville's Remembrall, Harry flies straight for McGonagall's window. The window visible in the wide shot has a horizontal beam that crosses the center vertical beam, yet the window visible in the close-up just has the vertical beam. The number of stones at the sides differ as well. (00:58:30)
Continuity mistake: While Harry and Hagrid stand beside Hogwarts Express, in the shot looking up at Hagrid as he takes the album out of his pocket, his thumb is on the back cover as he begins to say, "This is for you," yet in the next shot of Harry taking the album, Hagrid's thumb is on the front cover. (02:22:05)
Continuity mistake: On the Hogwarts Express, Hermione first watches as Ron tries to turn Scabbers yellow, she then joins them inside before she actually leaves and in these consecutive shots, her tie differs. (00:36:30)
Continuity mistake: Mr. Ollivander says, "I wondered when I'd be seeing you Mr. Potter," and as he climbs down the ladder Harry is standing at the middle of the desk, away from the corner. In the next shot as Mr. Ollivander searches for a wand case Harry stands at the corner of the desk. However, in the next shot Harry stands at the middle again. (00:25:30)
Revealing mistake: At the end of the film, when Harry is leaving on the Hogwarts Express, and the overhead shot shows the train pulling away from the station you can clearly see that Hagrid is of normal height, as the train roof is much taller than he is. (02:23:40)
Continuity mistake: In the scene where Harry, Ron, and Hermione are walking towards Hagrid after their exams, Hermione is carrying a brown satchel in her right hand. Then Harry says, "Why didn't I see it before!" and they run. While they are running she does not have the satchel in either hand, her empty left hand is visible in a few frames as she swings her hands at the side of her body. Then when they get to Hagrid she has the satchel in her left hand. (01:46:40)
Continuity mistake: At Platform 9 3/4, when Mrs. Weasley says, "All right, Percy, you first," as Percy walks in front of her she holds her bags in her left hand. Yet in the next shot as Percy still walks in front of her, she holds her bags in her right hand. (00:32:25)
Continuity mistake: When Dudley is told how many presents he has, and he asks, "How many are there?" a cut to him shows that his fringe is a bit untidy. Scene cuts to his Dad. When it cuts back to Dudley, his fringe is much neater. (00:05:04)
Revealing mistake: When the letters burst through the letter opening, which has been covered by a piece of wood, you can see that the piece of wood was pre-cut. (00:12:00)
Continuity mistake: At his home, when Vernon says, "Fine day, Sunday. In my opinion best day of the week. Why is that Dudley?" in the close-up his arms are crossed right over left. In the next wide shot, as Harry answers, Vernon's arms are crossed left over right. Yet in the next close-up, his arms are crossed right over left again. (00:10:40)
Continuity mistake: In the scene straight after the Quidditch match where Harry, Hermione and Ron are telling Hagrid about their suspicions of Snape, you will see all three are wearing scarves tied in different ways. When there's a change of shots, the creases in the scarves change. This happens mostly with Hermione's. (01:23:55)
Revealing mistake: When Harry and Hagrid are at Gringotts and are pulling up in the cart to Harry's vault, in the overhead shot you can see the various levels bellow them. In the next shot in the lower left corner you can see what appears to be blue screen just bellow the walking surface. (00:22:10)
Continuity mistake: When Hagrid and Harry step out the back door of the Leaky Cauldron, in the overhead shot there are many glass bottles on the floor, between the barrels. However, after Hagrid says, "Welcome Harry, to Diagon Alley," as they walk out the barrels are visible behind Hagrid and there are no glass bottles between the barrels. The stone ground differs in both shots too. (00:20:05)
Continuity mistake: In the scene where Harry and the Dursleys visit the zoo, the first shot you see of the snake, he is lying on a bare rock with only moss on it. He is also lying with his head facing the window, and his body is curving to the right. However, after Dudley walks away and the shot returns to the snake, his body is curving to the left and now there are plants directly behind him where there was only moss before. (00:06:00)
Continuity mistake: In the sea hut scene, when Dudley steals the cake, there's a shot of him eating it and his pyjama shirt is pulled up, then it cuts to Hagrid, and he says 'He'll be under the finest headmaster...' and it cuts back to Dudley, but his pyjama shirt is back down over his pyjama pants. (00:17:10)
Continuity mistake: While the first years are waiting at the top of the stairs just before being lead into the Great Hall for the first time, Ron's robes switch from being fully opened, to closed, then back again. (00:40:00)
Other mistake: In the scene where Professor Quirrell removes his headwrap to reveal the concealed Voldemort, Quirrell is obviously bald. However, if you carefully watch the scene with the troll, Quirell's sideburns are present after he shudders as the troll exhales, as they are in a couple of other shots. (01:10:43)
Suggested correction: The incident with the mountain troll took place on Halloween. The incident with Quirrell took place later in June. That is plenty of time for Quirrell to shave his head. Makes sense that he would as, I mean, I would rather shave my head if there was a guy on the back of it! Then I wouldn't have to worry about bumping his nose and him getting mad at me while using a comb. To be a mistake, we would need to see him with hair right before he is bald.
Continuity mistake: When Hermione is saying to Harry and Ron "You won't make a fool of yourself, it's in your blood," Harry and Ron have several books with them, but straight after, right before the staircase moves, they have no books in their hands. (01:00:35)
Continuity mistake: On Dudley's birthday, when Mrs Dursley wakes Harry and he sits up in bed, a cloth and hand brush are hanging next to him on the inside of the cupboard door. When Dudley shoves Harry back into the cupboard, there is now a cloth and a dustpan, but no brush. When the family arrive back from the zoo, and Mr Dursley locks Harry in the cupboard, there is no cloth, brush or dustpan. (00:04:10)
