Continuity mistake: In the scene where Hermione is coming out of the bathroom stall her head is down and you can see that the part in her hair is crooked, but when she is under the sink you can see that now her part is straight. (01:09:55 - 01:10:50)
Continuity mistake: The first wand Ollivander gives to Harry has a long slim handle with 5 or so grooves carved at the wand end. When Harry puts the wand down, the grooves are even with the binding of the book lying there. When Ollivander hands Harry the second wand, look to the left by the book and you can see that not only has the wand been moved, it is actually a different wand with a shorter, wider handle and only one groove at the wand end. (00:26:10)
Continuity mistake: When Harry and Ron are on the train to Hogwarts, we see a shot of the sweets Harry has bought. Note the position of Harry's sweatshirt and that the collar shows no defects. A couple of shots later, the sweatshirt appears to have moved and more of his left neck is showing. A few shots later, when Hermione arrives, there is another shot of the sweets arranged very differently. When Hermione points her wand at Harry, there is a small tear in his sweatshirt collar. (00:33:53)
Continuity mistake: At the beginning, Dumbledore is taking out all of the street lights, from one shot, the street light closest to Dumbledore on HIS right is still lit, but in the next shot, which is a close up of him taking the light, and shots later, the street light is out and he never "took" the light from that one. (00:01:05 - 00:01:55)
Continuity mistake: When Harry lands and gets off his broom after catching the Remembrall during the flying lesson, he starts running over a shadow of the castle. But in the next shot, it has either been shot at a different time of day, or he has gone past the shadow and has run further up the path. (00:58:55)
Continuity mistake: When Harry, Ron and Hermione are in the lavatory with the troll, the scattered wood pieces of the damaged cubicles change positions in consecutive shots throughout. For example, just before and after the troll drops Harry, in the close-ups of Harry the wood differs from the consecutive overhead shots. (01:11:35)
Continuity mistake: When Harry is on his way to the restricted section of the library under his Invisibility Cloak, we see a shot of his hand holding the lantern (the first shot in the scene). You can see the end of his jumper. In the next shot, however, the end of his jumper is under the cloak, and it had no time to get there between shots. (01:28:30)
Continuity mistake: When Harry, Ron, and Hermione are in the staircases, watch the pictures on the right: they are not moving, but when the camera changes all the pictures are moving. (01:00:50)
Continuity mistake: In the scene where the new students are walking to their rooms, there seems to be a whole lot more new students then there was in the sorting hat ceremony. (00:41:40 - 00:48:05)
Continuity mistake: In the chess scene, when Ron falls off the horse, he is lying on his side on the floor with one knee bent so that one foot is higher than the other. When Harry and Hermione run over to check on him, one foot is on top of the other. (02:05:15 - 02:06:00)
Continuity mistake: The very first scene where you see Hagrid on his motorcycle, he comes down and, from his position, you can tell he's gonna land way past the first house on the set. The next shot you see him touch down in front of that house. (00:02:15)
Continuity mistake: Malfoy has one tooth that is notably crooked. If you watch carefully, you'll see that it changes sides throughout the film. (00:40:55 - 01:43:50)
Continuity mistake: When Harry, Ron and Hermione are running to Hagrid's hut to tell him they know about the stone (just before they see Norbert) Hermione's hair is very long, but by the time they get inside his hut and take off their cloaks, her hair is much shorter. (01:38:40 - 01:39:25)
Continuity mistake: When Harry sneaks into the restricted section of the library with his lantern, he puts the lantern down on the ledge and the light doesn't even flicker, you can tell it's a sort of lightbulb, not a candle. (01:29:10)
Continuity mistake: In the scene in the library's restricted section, Harry puts down his cloak and then his lamp. The lamp is several inches away from the cloak. When Filch enters Harry grabs the cloak and suddenly the lamp is now on top of the cloak, causing it to fall. (01:29:10)
Continuity mistake: When Professor McGonnagall is talking to the children before their sorting, you can tell when the camera is on her that the lighting is candle-like (note the flicker). When the camera cuts to the children, there is no flicker (check out Hermione). (00:39:50)
Continuity mistake: When all of the letters are arriving from Hogwarts at the Dursleys' house, it is obvious that the ones flying around the room are just single pieces of paper and not thick envelopes containing letters. (00:11:25)
Continuity mistake: In the scene where the pupils are waiting on the stairs before being sorted into their houses, Malfoy speaks to Harry and is clearly at the top of the stairs. However as the pupils go into the dining room, Malfoy is nowhere to be seen in at least the first 30 pupils. (00:41:15)
Continuity mistake: When Harry and Ron are sat on the train, Ron's hair begins with a centre parting, but soon changes to a side parting. (00:32:59)
Continuity mistake: When the three heroes first go into the forbidden corridor and are spotted by Filch's cat, they run away, through the large horizontal corridor which must be at least 40 metres long (since we are given two long shots of it and neither of them connects by any physical object). They hide behind a wooden door which they close afterwards. When Filch looks in the other end of the corridor then leaves and we hear a very silent click, Hermione says 'Filch is gone.' The door they're behind does not seem to be open at all, and even if it is open a bit on the right side, Hermione's on the left side of it so she can't see whether Filch is gone or not. And can you hear a silent click of a closing door from forty metres? (01:01:45)
