List of differences between the Harry Potter books and films

Below are a list of changes made to the stories of the Harry Potter books when they were adapted into feature films.

1. House Points

 * In the film, House Points play a major role only in the Philosopher's Stone. In the other films, almost all mention of house points are omitted (except for one instance in Prisoner of Azkaban where Snape takes 5 points from Gryffindor).

2. Missing Characters

 * Some characters that play a secondary or even active role in the books are completely omitted or mentioned only. These include:
 * Charles Weasley
 * Peeves
 * Ludo Bagman
 * Bertha Jorkins
 * Cuthbert Binns

1. The Boy Who Lived

 * The film begins with Harry's arrival at Privet Drive. As a result, everything that precedes this point in the book is omitted in the film, which includes:
 * Vernon Dursley's day at Grunnings and his encounter with the wizards during his lunch break on the day before Harry arrived.
 * Vernon Dursley noticing Minerva McGonagall in her Animagus form earlier in the day, thinking she was reading a map.
 * The existence of Ted and Jim McGuffin.
 * At the start of the novel, Minerva McGonagall in her Animagus form had been observing Vernon Dursley prior to her meeting with Dumbledore and Hagrid. While this scene was omitted from the film, it was referenced when McGonagall voiced her objections in leaving Harry in the Dursley's care when she said she had "watched them all day".
 * In the film, when Albus Dumbledore leaves Harry Potter on the doorstep of the Dursleys' house, he says, "Good luck, Harry Potter." In the book, he just says, "Good luck, Harry." This is likely because of the aforementioned omissions.

2. The Vanishing Glass

 * When Dudley counts the presents in the book, he says there are 36 and that is two less than last year, although Aunt Petunia then shows him the present he has missed out. In the film, it was Uncle Vernon who counted the presents, and while the count remains at 36, Dudley had 37 presents last year instead of 38.
 * In the book, the Dursleys and Harry are accompanied to the zoo by Dudley's friend Piers Polkiss. He is omitted in the film.
 * The Dursleys attempting to have Harry stay with Arabella Figg is omitted, as well as the mention of her having broken her leg and also the possibilities of Harry being watched by Vernon's sister, Marge who hates Harry and Petunia's friend, Yvonne who is on vacation in Majorca.
 * In the book, before going to the zoo, Vernon tells Harry that if any funny stuff happens he will be in the cupboard from then until Christmas, while in the film, Vernon tells Harry that if any funny business happens, he won't have any meals for a week (although this happens in the book after the zoo incident, when Vernon says to Harry to go to his cupboard and stay there with no meals).
 * In the film, Vernon pulls Harry by the hair demanding that Harry tell what happened; when Harry explains, he is thrown into and locked in the cupboard by his uncle, who says to him through a small vent: "There's no such thing as magic!"
 * In the book, the glass of the snake tank remains vanished. In the film it returns, trapping Dudley in the tank.
 * The Keeper of the reptile house who asks where the glass went is omitted from the movie since the glass came back and trapped Dudley inside the tank.
 * Harry states in the second film that the snake at the zoo was a python (But there was a sign in the film saying 'Burmese Python'). The snake at the zoo is said to be from Burma. In the novel, it is a boa constrictor from Brazil, not a python from Burma. However, both the novel and the film reveal the snake was bred in captivity.
 * In the book, the snake addressed Harry as "amigo" when thanking him for freeing it - presumably, a nod by JK Rowling to its South American ancestry as "amigo" means friend in Portuguese and Spanish. In the film, the snake simply says "thanks".

3. The Letters From No One

 * Dudley appears to know about Hogwarts, as he stares worriedly at Harry like his parents do. In the books, Dudley does not know about magic when Harry gets his letter.
 * The scene when Harry gets Dudley's second bedroom is omitted. He does get the room in the second film, with the latter film implying that the Dursleys supplied Harry with the room after the First Year.
 * The scene where Harry and the Dursleys go to a random hotel to get away from the letters was omitted from the movie, so instead they went straight to the hut.
 * Because of this, Dudley's line of "Daddy's gone mad, hasn't he?!" was moved to immediately after Uncle Vernon declares that they are going to move far enough away to ensure that the owls can't find them. In the book, Dudley says this line only after Vernon pauses driving long enough to do a glance around to see if any owls are following them on a bridge.
 * The scene with Harry and the Dursleys using the rowboat of the toothless old man to get to the hut is omitted; Therefore, the old man is also omitted from the film, but he appears in concept artwork only.

4. The Keeper of the Keys

 * In the book, when Hagrid first met Harry on the island he knew who he was right away, while in the film Hagrid initially mistook Dudley for Harry until Dudley corrected him.
 * In the book, Vernon Dursley warns Dudley not to receive or eat anything that Hagrid gives him when he was making sausages for Harry. In the film, Vernon doesn't mention this to Dudley, as Dudley is later seen eating some of Harry's birthday cake, which Hagrid makes him stop by giving him the pig's tail.
 * In the book, Hagrid grabs the gun and ties it into a knot. In the film he grabs the barrel of the gun and bends it upwards only. The movie also has the gun discharging shortly afterward, something that never happens in the book.
 * In the book, Harry does not say "Thank you" to Hagrid when he gives him a birthday cake, but in the film, he does.
 * In the book, Hagrid immediately curses Dudley into getting a pig's tail after the former threatened Uncle Vernon upon the latter insulting Dumbledore. In the film, he instead curses Dudley after noticing that the latter was eating Harry's cake.
 * Hagrid never tells Harry about his being expelled from Hogwarts in the film.

5. Diagon Alley

 * Hagrid tells Harry about the death of his parents while he is still with the Dursleys on the island in the sea in the book. However in the film, Harry asks about this at the Leaky Cauldron, and it is here that Hagrid tells Harry about his parents.
 * In the film, Hagrid does not tell Harry that he was expelled from Hogwarts but allowed to remain as gamekeeper at the school, while he does in the book; this would not be revealed until the next film.
 * This scene is also the first time Voldemort is mentioned, while in the book he is mentioned by Dumbledore and McGonagall at the beginning (though he is referenced with talk about rumours).
 * In the book, Quirrell does not have his turban until after his failed attempt to steal the Philosopher's Stone from Gringotts. In the film, however, Quirrell has his turban before the robbery. This change is indicated by the fact that he shakes Harry's hand at the Leaky Cauldron in the novel, but does not wish to in the film. However, not wanting to shake Harry's hand cannot be due Voldemort sharing Quirrell's body, because as Quirrell dies, he does not understand what is happening to him (he yells, "What is this magic?!").
 * In the novel, when Harry buys his wand, Hagrid is with him. But in the film, Hagrid is not present, having gone to buy Hedwig. Also, in the novel Harry is with Hagrid when he buys Hedwig, before going to Ollivanders.
 * In the book, Harry names Hedwig from a History of Magic book. In the film, it is not mentioned where the name was chosen from. Hedwig's name isn't even mentioned in the film.
 * In the novel, when Harry buys his wand, he tried many wands before Mr Ollivander thought of the 11 inch holly wand with a phoenix feather core, but in the film he only tried two wands before Mr Ollivander thought of the right wand. Also in the novel, when Harry waved the wands, they didn't do anything, but in the film when he waved the wands, they blew papers and boxes of wands off the shelves and broke a vase.
 * Malkin is omitted despite her name appearing on a sign.
 * In the book Harry first met Draco Malfoy in Diagon Alley while shopping and later learned who he was on the Hogwarts Express, where Harry chose not to befriend him after Draco insulted Ron Weasley. In the film, both these events occur at Hogwarts before the Sorting.
 * In the book Harry first hears about Quidditch from Draco Malfoy while in Diagon Alley before Hagrid explains what it is after Harry met up with him. In the film this was instead moved to Hogwarts during Harry's first flying lesson after Madam Hooch mentions it when she has to take Neville Longbottom to the hospital wing.
 * After his first visit to Diagon Alley, Harry returns to live with the Dursleys for several weeks and Vernon Dursley drives him to the train station. In the film, Harry went to the train station with Hagrid just after buying his school supplies.
 * The character Peeves is omitted, although a scene was filmed for him, but ended up being cut, even being omitted from the current DVD release. Peeves never appeared in any of the films.

6. The Journey From Platform Nine and Three-Quarters

 * In the book Harry first learns about the connection between Dumbledore and Flamel on the back of his chocolate frogs card. In the movie, it is Hermione who comes across the name in a book she picked up for 'light reading'. In a deleted scene however you see Harry finding the name on a chocolate frog card after which the trio runs off to the library, so it only appears as a "mistake".
 * In the book, Neville comes into the compartment where Harry and Ron are sitting asking if they have seen his toad, which was omitted. Later Hermione shows up again with Neville asking the same question. In the film, Hermione shows up by herself asking if anyone has seen a toad, and that a boy named Neville has lost one.

7. The Sorting Hat

 * In the book, before the sorting begins, the Sorting Hat sings a song, but this does not happen in the film.
 * Sorting was done alphabetically in the novel, and out of order in the film. Also, only Hermione, Malfoy, Susan Bones, Ron and Harry are seen to be sorted in the film, although presumably the others were sorted after Harry, even though this is not shown.
 * In the novel, after the sorting, Dumbledore stands to say a few words and comically utters a few random words at which point supper begins. This is omitted in the film, with Dumbledore giving the start of term notices instead.
 * Harry learns that only Slytherins go bad from Hagrid in Diagon Alley. In the film, he learns it from Ron during the Sorting ceremony.
 * In the book Percy Weasley wears glasses but throughout the films, he is seen without them.
 * Hedwig's name is never mentioned, except in a deleted scene. The same goes for Mrs Norris. Both names are mentioned in later films.

8. The Potions Master

 * In the book, Harry and his friends attend Charms class at some point before Potions, but in the film, they attend it much later.
 * In Potions, when Harry is unable to answer Snape's questions, he says that Hermione should try and answer instead, he takes 1 point from Gryffindor and then he loses another point for not telling Neville not to put quills into his cauldron during potion-brewing. In the film, this scene appeared as a deleted scene with Snape coming down to sit in front of Harry giving him the answers, then takes 5 points from Gryffindor for Harry's cheek and the scene with potion-brewing is completely omitted from the film and this deleted scene.

9. The Midnight Duel

 * In the novel, during the Flying Lesson after Neville breaks his wrist, Draco Malfoy says he might leave Neville's Remembrall on a tree for him to find, but in the film, he suggests to leave it on the roof.
 * There is a moment added in this scene of the film that never happened in the book: While everyone is constantly repeating 'Up!' to get their brooms into their hands, Ron's flies up a little too fast and hits him in the face.
 * In the novel, when Professor McGonagall arrives to take Harry, she looks frustrated and one of the Patil twins and Ron try to explain what happened, but in the film, McGonagall is calm and calls Harry by his name and then asks him to follow her.
 * When McGonagall takes Harry inside to make him a Seeker, Oliver Wood is attending Charms Class with Professor Flitwick, but in the film, he is having Defence Against the Dark Arts with Professor Quirrell.
 * In the film, McGonagall tells Wood she has found him a Seeker outside Quirrell's classroom, but in the novel, she takes Oliver and Harry to an empty classroom where they find Peeves writing rude words on a blackboard.
 * In the novel, McGonagall mentioned to Harry in front of Oliver Wood that James Potter was a Chaser for the Gryffindor Quidditch team when he was at Hogwarts, while in the film, Hermione escorts him (and Ron) to a trophy window where Harry sees his father's name on a trophy badge saying that he was a Seeker.
 * The scene where Malfoy challenged Harry to a duel, but had actually tricked him by tipping off Filch was omitted. Instead, Harry, Ron and Hermione see Fluffy in the Forbidden Corridor after their escape from Filch and Mrs Norris when accidentally entering the third floor. In the book, Neville was also with them when first meeting Fluffy.

10. Hallowe'en

 * In the book, Harry's first Quidditch training session takes place at 7:00 p.m., but in the film, it starts at daytime at an unknown period. The time is unknown because the scene where Harry receives the message along with the Nimbus 2000 is cut from the film.
 * In the film, when Oliver Wood was explaining the rules of Quidditch to Harry, Wood said "You catch [the Golden Snitch], Potter, and we win." However this is inaccurate because catching the Snitch only awards 150 points and if the opposing team is leading by more than 150 points, the team that caught the Snitch will lose (the odds of this happening are very low). In the book, however, Wood said, "Whichever Seeker catches the Snitch wins his team an extra hundred and fifty points, so they nearly always win" which explains it more because he said "nearly always win", not "we win".
 * In the book, Harry's receives his Nimbus 2000 before his first training session with Oliver Wood and before his encounter with the troll but in the film, he receives his broom after these two events occur. Due to this difference, Harry flies the Nimbus 2000 in the book during training, but in the film, he doesn't have the Nimbus 2000 or any other broom and therefore doesn't fly.
 * Due to Peeves's omission from the film, Ron suggests that people are playing jokes since he states that a troll couldn't get in on its own because they're really stupid. In the book Ron has the feeling that it could've been Peeves who let the troll in for a Hallowe'en prank.
 * In the book, when Hermione is crying in the bathroom and Professor Quirrell announces that there is a troll in the dungeon, Harry and Ron go to find her and see the troll going into a room (not realising it's the bathroom) and lock the door thinking they've locked the troll into some random room until they hear Hermione screaming and realise they've locked the troll in with her in the bathroom. In the film Harry and Ron see the troll's shadow emerging, they hide and watch the troll go into a room, and Harry says, "It's going into the girls' bathroom!" and they go in to save Hermione.
 * In the novel, when Ron tries to levitate his feather in Charms class and is doing it incorrectly, Hermione tells him to make the gar nice and long, while in the film, she tells him the pronunciation is Leviosa and not Leviosar.
 * Also, in the film, when Ron doesn't do the incantation correctly, he waves his wand up and down very quickly, when Hermione tells him to stop because he's going to take someone's eye out. This dialogue did not appear in the book.
 * In the film, Seamus Finnigan's feather blows up while in Charms class, and later, his cup of water blows up while he is trying to turn it into rum. The act of Seamus's works blowing up on him would become a recurring joke throughout the film series.

11. Quidditch

 * The scene with Harry in possession of the book outside school and Snape takes it and deducts 5 points from Gryffindor is omitted. This also omits the scene where Harry tries to get the book back and Snape is bandaging his wounded leg.
 * In the book during the Gryffindor-Slytherin Quidditch match, Gryffindor's score is 20 and Slytherin's is 60 until Harry wins 150 points for catching the Golden Snitch. In the film, both Gryffindor and Slytherin were tied with 20 until Harry caught the Snitch which also resulted in Harry winning 150 points.
 * In the book, when Hermione tries to stop Snape from jinxing Harry's broom (when it is really Quirrell), she accidentally knocks Quirrell over as she runs by him. In the film, when the other wizards near Snape see that he is on fire, one of them shoves Quirrell to the ground, breaking his eye contact.
 * In the book, Hagrid says that he bought Fluffy from a "Greek chappie" while in the film, Hagrid says he bought Fluffy from an "Irish feller".

12.The Mirror of Erised

 * Irma Pince is omitted.
 * Fred and George Weasley having bewitched several snowballs to follow Quirrell around and then to hit him on the back of the head (and into Voldemort's face) is omitted.
 * Draco Malfoy insulting Ron's family, his poverty and Hagrid's hut in front of him is omitted.
 * In the novel, Harry receives a wooden flute from Hagrid, a fifty pence piece from his Uncle Vernon and Aunt Petunia, a jumper from Molly Weasley, a large pack of Chocolate Frogs from Hermione and the Invisibility Cloak from Dumbledore. In the film, Harry only receives the Cloak, but the jumper appears in a deleted scene.
 * In the novel, Ron doesn't seem to know what the cloak is, but in the film he realises that it's an Invisibility Cloak when Harry puts it on.
 * In the novel, after Harry tries on the Invisibility Cloak, he reads the message that came with the package, but in the film, Harry reads the message before trying the cloak on.
 * Also, in the film, the last line of the Christmas note ('A Very Merry Christmas to you') is omitted.
 * In the novel, Harry sees his parents and his grandparents in the Mirror of Erised, but this was changed in the movie to where Harry just sees his parents.
 * Harry sees the Mirror of Erised thrice on Christmas instead of three days like in the book. But the part where Harry didn't feel like having fun appeared in a deleted scene.

13. Nicolas Flamel

 * The Hufflepuff-Gryffindor Quidditch match, where Snape is the referee, is omitted in the film. This is where after the victory against Hufflepuff, Harry sees a hooded figure rush off into the forest as he is about to put away his Nimbus 2000 in the broomshed and hops back on his broom to follow them into the forest, encountering Snape and Quirrell and overhearing their conversation. Instead in the film, Harry hears Snape talking to Quirrell in a corridor near the library before stumbling upon the Mirror of Erised.
 * Also due to this change, in the film Filch interrupts Snape and Quirrell's conversation by stating there was a student out of bed due to having Harry's lamp. In the book however after Harry dropped the lamp while in the library's Restricted section, Filch went to get Professor Snape just as Harry is sneaking into the room where the Mirror of Erised is stored to hide.
 * Since the Quidditch match was omitted, the part of Ron and Neville Longbottom getting into a fistfight with Draco, Crabbe, and Goyle on the stands during the game is also omitted.
 * In the film, Harry, Ron and Hermione discover the link to Nicolas Flamel and the stone through a book, rather than Albus Dumbledore's Chocolate Frog Card, although a deleted scene shows them discovering the connection through a chocolate frog card, but it was switched when edited).
 * In the book, Nicolas Flamel's name is spelled Nicolas. In the film, an "H" is added spelling it "Nicholas Flamel".
 * In the film, when Harry, Ron and Hermione are reading the information about the Philosopher's Stone, Nicolas Flamel's wife Perenelle is not mentioned and another fact that isn't mentioned is about Nicolas and Perenelle enjoying a quiet life in Devon.

14. Norbert the Norwegian Ridgeback

 * The part where the dragon Norbert is sent to Charlie Weasley is omitted. Instead, Hagrid later revealed to the Trio that Dumbledore sent him to Romania (whether to Charlie or not it is not revealed, although it is mentioned in the film that Charlie works with dragons in Romania).
 * When Harry and Hermione get detention, it is because they left the Invisibility Cloak in the Astronomy tower while sending Norbert to Charlie Weasley and were caught by Argus Filch at the foot of the stairs. Neville was also given detention for being out of bed because he was trying to warn Harry about Malfoy and was caught by Professor McGonagall. In the film, they get detention because Draco Malfoy saw them in Hagrid's hut past curfew (which is similar in the book, except that Draco did not inform McGonagall). Ron is also with them in the film, while in the book he was recovering in the hospital wing after being bitten by Norbert. Therefore, in the film, Ron gets detention instead of Neville.

15. The Forbidden Forest

 * Professor McGonagall takes 50 points from Slytherin instead of 20; She says "50 points will be taken. Each." before saying "All four of you will receive detention". Until she says that, Malfoy did not know that he would also be getting detention. In the book, Malfoy is caught by McGonagall before Filch catches Harry, Neville, and Hermione.
 * In the book version, it is mentioned that the other Gryffindors and Hufflepuffs/Ravenclaws were very upset with the Trio having lost a lot of points. This is not shown in the film (excluding Gryffindor's initial disappointment in having lost the House Cup at the end), however according to a Magazine article on the DVD release of the film, there was a scene filmed of Harry and Ron looking at the House Point Hourglasses in the Great Hall, but was not included in the movie or on the deleted scenes of the DVD.
 * Other than Ron serving detention in Neville's place for the film Harry is paired with Draco and Fang initially when the group divides into two groups at the start of detention. In the book Harry is initially paired with Hagrid and Hermione when the group divides up, but after Draco pulls a nasty trick on Neville, Hagrid is forced to swap Harry and Neville between each group.
 * Ronan and Bane are omitted from the film. Firenze is the only centaur who appears. Bane later appears in the Order of the Phoenix film (but is not identified), while this would be Firenze's only appearance in the films.
 * In the book, Harry gets a ride on Firenze's back and he escorts the boy back to Hagrid, Draco, Fang, Hermione and Neville. In the film, the ride is omitted and Draco and Fang return to the scene of the crime with Hagrid, Ron and Hermione to find Harry, Firenze and the dead unicorn.

16. Through the Trapdoor

 * In the book, when Harry, Ron and Hermione tell Professor McGonagall they have to see Professor Dumbledore, Harry almost says that Snape is going to try and steal the Philosopher's Stone, but then corrects himself and says someone, but in the film, Harry just says that someone is going to try and steal it.
 * Due to Peeves' omission from the movie, the scene where Harry manages to drive him away by impersonating the Bloody Baron while under the Invisibility Cloak with Ron and Hermione is omitted.
 * Harry, Ron, and Hermione never have the flute that would put Fluffy to sleep, as they do in the book. Instead the trio enters the room under the Invisibility Cloak, spotting there a self-playing harp enchanted by Quirrell. Fluffy is asleep until the spell wears off. Also in the novel, the trio find a harp under Fluffy's paw, but in the film the harp is standing up, playing, at a distance away from Fluffy instead of being under its paw.
 * In the film, when Harry, Ron, and Hermione fall into the Devil's Snare, Hermione and Harry escape by relaxing, and Hermione saves Ron with Lumos Solem. In the novel, Hermione was able to find a damp wall and free herself before the plant had a firm grip on her. She also frees both Harry and Ron with Bluebell Flames.
 * Likewise, in the novel it is Hermione who panics during the incident with the Devil's Snare and Ron who has to snap her out of it. In the film, this is reversed - Ron panics and Hermione calms Ron down.
 * In the novel, Harry, Ron, and Hermione, each seizes a broomstick and kicks off into the air to chase the Winged Keys, while in the film, only Harry does, as there is only one broom. This could be a deliberate choice by the filmmakers to clearly show each of their skills (Hermione with spells, Harry being a Seeker, and Ron with Chess).The same is for the PC game and.
 * In the book, the chess game depicts the pieces simply knocking each other out and dragging captured pieces off the edge of the board. In the film, the chess game was depicted with the pieces destroying each other (presumably to be fixed with Reparo at the end of the game).
 * On the way to the Philosopher's Stone, each obstacle was created by a teacher. While probably the same case in the film, this wasn't directly acknowledged; In the film, Quirrell's second mountain troll and Snape's Potion Riddle are omitted, although they are present in the video game. Because of these omissions, Hermione stays with Ron after Ron was injured in the chess match at McGonagall's room instead of travelling with Harry as far as the Potions room before heading back. This is odd, since Hagrid tells Harry, Ron, and Hermione that Snape is one of the teachers protecting the stone. However, Snape's obstacle appears in 'Disc 2: Special Features' of the DVD. It is also possible that Snape could be a sort of "private investigator" or "security guard" who keeps an eye out for anyone trying to get to the Stone.

17. The Man with Two Faces

 * In the book, Quirrell was aware that Hermione was the one who set Snape's robes on fire since he mentioned she had knocked him over during the Gryffindor-Slytherin Quidditch match, but in the film, he doesn't appear to know as she was under the stands and another wizard had instead knocked Quirrell over.
 * Quirrell does not mention Snape being at Hogwarts with Harry's father as students who loathed each other.
 * In the book, Quirrell turns around so that Voldemort is facing Harry. In the film however, Quirrell does not turn around, and Harry sees Voldemort's reflection in the Mirror of Erised instead.
 * In the book, Quirrell snaps his fingers which causes ropes to appear out of thin air and wrap themselves around Harry. This is omitted from the film, and when Harry tries to escape Quirrell/Voldemort with the Stone in his pocket by running back up the stairs the way he came, Voldemort shouts "Stop him!" and Quirrell snaps his fingers which causes fire to appear all around the room so Harry can not escape.
 * In the film, Harry's parents appear in the Mirror of Erised and Voldemort says he and Harry can bring them back if he gives Voldemort the Stone in return. This did not happen in the book, but instead Voldemort tells Harry that his (Harry's) mother needn't have died because she was trying to protect him and says that Harry should give him the Stone unless he would have wanted Lily to have died in vain.
 * In the book, Voldemort kills Quirrell by leaving his head, causing him to die. In the film, Harry kills Quirrell by grabbing his face, causing him to turn to dust.
 * In the book, when Harry touched Quirrell, Quirrell's skin blistered wherever Harry touched. In the film, when Harry touched his hand, Quirrell's hand turned to stone and crumbled. Also, when Harry grabbed his face, it made his whole body demolish and Voldemort escaped. This is what knocked Harry out.
 * In the book, Harry Potter is unconscious when Quirinus Quirrell dies, while in the film, Harry watches Quirrell die. This creates a continuity error with his ability to a see a Thestral in the film version of, since Harry could not see Thestrals until he saw Cedric Diggory die. This could also be due to the film being released before the Order of the Phoenix book was published, and so the film crew wouldn't have known about what would happen in later books.
 * Poppy Pomfrey is omitted but there is an unknown nurse who appeared before Albus Dumbledore took a bite of Bertie Bott's Every Flavour Beans.
 * Once again, Nicolas Flamel's wife Perenelle is not mentioned when Harry asked about Flamel dying.
 * In the book, Harry reunites with Ron and Hermione in the hospital wing when they come to visit him, while in the film, he reunites with them when he finds them standing at the top of a staircase.
 * In the book, Hagrid gives Harry a photo album of his family at the hospital while in the film version, he gives it to him at the end of term when about to board the Hogwarts Express.
 * In the novel an epilogue shows Harry and his friends return to their families who are waiting for them including the Dursleys, In the film it is omitted.

Character physical appearance
Some notable differences exist between key cast members of the film, compared to the way their characters are described in the books:
 * Hermione is described as having bushy hair and prominent front teeth, while actress Emma Watson has normal sized teeth and her hair, though bushy in this film, isn't as bad as described in the book (and later films do away with bushy hairstyles altogether).
 * Harry has green eyes, but actor Daniel Radcliffe, who has blue eyes, was unable to wear contact lenses, due to an allergic reaction (except in one scene - see below). Harry is also described as having messy black hair, in the film his hair is very dark brown and not particularly messy.
 * Ron is described as tall and lanky, while Fred and George are shorter. Actor Rupert Grint is not tall and lanky in this initial film, while two tall actors (James and Oliver Phelps) were cast for Fred and George are. Also, Ron is supposed to have blue eyes, but Rupert has green. Ron in the book is also described as having big hands and feet, as well as a long nose; actor Rupert Grint has a regular sized nose and hands.
 * Petunia Dursley has blonde hair in the book, but the actress in the film has dark brown/black hair.
 * In the scene after the Forbidden Forest, Hermione says Voldemort's name. In the book, she refers to him as "You-Know-Who". This also creates a continuity error where she says Voldemort's name in the fifth film as if she has never said it before.
 * Dudley Dursley is described to have had blonde hair in the books, while the actor has brown hair.

The Blu-Ray edition of Philosopher's Stone includes commentary from director Chris Columbus that reveals that the final scene of the film -- where Harry, Hermione and Ron depart on the Hogwarts Express -- was the first scene shot. As such, some changes in Harry and Hermione's physical appearance can be seen. Emma Watson was initially fitted with prosthetic teeth to make her look more like the book version of Hermione, but this was abandoned as impractical after the first scene was shot. Columbus says editing made the buck teeth less obvious, but they are still visible during a brief bit of dialogue. Actor Radcliffe, meanwhile, was fitted with green contact lenses which are clearly visible in close-ups, but they weren't used after this first day of shooting because they irritated Radcliffe's eyes.

1. The Worst Birthday

 * The book begins in the morning of Harry's birthday. The film begins in the evening of the day the Masons' visit, omitting Dobby in the hedges and additional quarrels between Harry and the Dursleys. However Vernon does say that Harry is not thankful; Vernon says they cared for Harry since he was a baby, gave him their good food, and giving him Dudley's extra bedroom because they were so merciful.
 * On a related note, the film implies that the Dursleys' giving Harry Dudley's old bedroom occurred after his first year of Hogwarts, when he actually was given the bedroom right before Harry's new schoolyear in the previous book, in an attempt to dissuade the acceptance letters to Hogwarts addressed to Harry.
 * The scene where Harry is banned by the Dursleys from saying the word 'magic' is not in the film.

2. Dobby's Warning

 * In the book, when Harry enters his room, Dobby sits on his bed quietly. In the film, Dobby is jumping on his bed and laughing.
 * Dobby does not mention that Voldemort, or a possible brother could be a suspect, as in the book version.
 * In the books, whenever Dobby disapparates, the usual loud crack is heard. But in the films, Dobby appears and disappears quietly, however it differs from film to film how he does it. In this film he fades, like if the wind took him.
 * The film shows Dobby levitating the cake into the sitting room and dropping it on top of Mrs Mason. In the book, however, the pudding dropped by Dobby in the kitchen, causing it to explode all over Harry, not Mrs Mason. Also in the film. Mr Mason tastes the cake, using a finger.
 * While the reason in the film for the Masons' departure was due to the cake dropping on Mrs Mason, in the book it was due to Mrs Mason's fear of birds when an owl sent by the Ministry of Magic arrived at the Dursleys in regards to the illegal use of the Hover Charm that was performed.
 * A scene is cut where the Ministry sends a letter to reprimand Harry for violating the Decree for the Reasonable Restriction of Underage Sorcery, which informed the Dursleys of this rule. This explains in the following film how Vernon Dursley already knew that Harry is not allowed to perform magic outside of school. Since this scene was not included in this film, it caused a continuity error with the future films.
 * In the book, Uncle Vernon tells a man to fit the bars on Harry's window, but in the film, Uncle Vernon fits the bars on Harry's window himself.
 * Harry's nightmare of himself being in a zoo cage is omitted.

3. The Burrow

 * In the film, Ron wishes Harry a happy birthday when they fly away from 4 Privet Drive. Ron doesn't say this in the book as Harry's birthday was the same day the Masons visited. It should be mentioned that in the film the Weasleys gets Harry out the same evening, while in the book they saved him from the Dursleys early in the morning, next day.
 * In the book, the Dursleys were woken up by Hedwig's screech. In the film, they're woken up by the noise of the bars falling into the grass.
 * In the book, Harry's trunk is locked in the cupboard under the stairs and Fred and George sneak in the house and pick the lock of both Harry's room and the cupboard. In the film, Harry's trunk is in his room and Fred and George don't sneak in the house.
 * In the book, Harry forgets Hedwig, but he gets to her just in time. In the film, Harry doesn't forget anything.
 * When Harry was escaping from the Dursleys, the book states that all of the Dursleys tried to prevent him from escaping, only to end up hanging from the window. The film depicts only Uncle Vernon trying to prevent him from escaping, which results in him falling out of the window and landing into a bush. The fall of Vernon from the window was a comic effect created to make the scene more comedic.
 * In the Flying Ford Anglia the Weasley brothers suggest that Dobby could be an untrustworthy servant of the Malfoys. This is omitted from the film.
 * In the book, when Harry arrives at the Weasleys' home, Mrs Weasley makes her sons "de-gnome" the garden. This scene is omitted from the film.

4. Flourish and Blotts

 * The scene where Harry listens to Lucius and Draco Malfoy's business with Borgin is cut. It is included in the deleted scenes section of the DVD. (An alternate version of the same scene, where Harry is caught by Borgin was also filmed and included on the DVD.) In this scene Lucius almost hits Draco two times with his walking stick when telling him not to touch anything. This could be meant in reference to the cursed necklace.
 * In the book, Mr Weasley repairs Harry's glasses in Diagon Alley, but in the film, Hermione repairs them and the knowledge of her using under-age magic is unnoticed. Though it is revealed in one of the following books that the Ministry of Magic only knows where there is used magic and not who it is that is using magic. (This explains why Harry is believed to be the one to perform the levitating spell on the pudding though it is Dobby. Also this could explain why Hermione didn't get a letter on the Hogwarts Express in the previous film; too many students and pre-students, plus two adults.)
 * The part where Arthur Weasley fights with Lucius Malfoy in Flourish and Blotts is omitted. Instead, they only exchange tense words. Lucius also mentions that he will "see you [Arthur] at work", implying that he works at the Ministry of Magic in the film. On a related note, Lucius only subtly puts the diary into Ginny's cauldron after looking at and mocking her hand-me-down textbook in the film. In the original, he gives the book back to her after fighting her father, the diary stealthily included in it, after the fight.
 * When they meet in Diagon Alley, Hermione chides Lucius Malfoy for not using Voldemort's name. (In the first two films, Hermione shows no fear of the name Voldemort, speaking it without difficulty in the first film) In the books, Hermione never uses the name Voldemort until the fifth novel, and even then it requires courage. The films have a bit of a continuity issue on this point as the fifth film shows her getting the courage to say "Voldemort".
 * Arthur Weasley asks Harry about escalators in the book, but in the film, he asks about rubber duckies.

5. The Whomping Willow

 * Harry and Ron get to Hogwarts with almost no problem in the book, whereas in the film they nearly get hit by the Hogwarts Express, and Harry nearly falls out of the car.
 * In the film, Argus Filch finds Harry and Ron and takes them to Professor Snape's office, but in the book, Snape himself finds Harry and Ron and takes them to his office.
 * In a deleted scene that follows this scene Harry finds a letter about a Kwikspell course addressed to Filch and hands it over. In the book Harry finds this letter in Filch's office.
 * In the book, Ron and Harry eat sandwiches in Snape's office after being caught by Snape. Ron wants to know which house Ginny was placed in and Professor McGonagall tells him she's a Gryffindor. This scene is not in the film, but Ron does find out about Ginny being in Gryffindor from his mother's howler.

6. Gilderoy Lockhart

 * In the book, Mrs Weasley's howler to Ron is much lengthier and mentions Harry in it. In the film the howler message is much shorter and Harry is never mentioned, instead a part of the howler was directed to Ginny. Also in the book, there is no mention of howlers folding themselves into a pair of lips.
 * Howler bursts into flames in the book but rips itself into shreds in the film, with a grrr-sound.
 * Lockhart's scene with Professor Sprout before the first Herbology lesson of the year, in which he implied that he knew more about caring for Whomping Willows than she did, is not shown.
 * The scenes in which Lockhart lectures Harry for giving out autographs (due to Colin's actual request in the book) and makes him late for Herbology, are not seen in the film.
 * Defence Against the Dark Arts shows both Hufflepuffs (Justin Finch-Fletchley and Susan Bones, for example) and Slytherins (Malfoy, Crabbe, and Goyle) in the same class as the Gryffindors.
 * Second-year Gryffindors have Herbology only with the Hufflepuffs in the book, but also with the Slytherins in the film.
 * When the Pixies are loose in Lockhart's class, there are several differences that occur:
 * In the novel, several pixies shoot straight through the window, shower the back row with broken glass. The rest proceeded to wreck the classroom more effectively than a rampaging rhino, grab ink bottles and spray the class with them, shred books and papers, tear pictures from the walls, up end the waste basket, grab bags and books and throw them out of the smashed window; within minutes, half the class was sheltering under desks and Neville was swinging from the iron chandelier in the ceiling, half the students hide under desks, then the bell rings and everyone leaves. In the film, the chaos consists of book throwing, book page tearing and Neville hung onto the chandelier. Also, in the film, no one hides under the desks and everyone leaves on their own accord to save themselves from the Pixies.
 * The Pixies throw Lockhart's wand out the window in the book. In the film, this does not happen and instead, one of the Pixies snatches Lockhart's wand and breaks off the dragon skeleton hanging from the ceiling.
 * Also, in the film, there is an added moment when the Pixies steal a portrait of Lockhart and he tries to get it back, but fails.
 * In the novel, Lockhart hides under his desk, but in the film, he doesn't. Also Neville falls from the chandelier in the book and misses Lockhart. In the film, Neville remains hanging from the chandelier.
 * In the novel, Harry, Ron and Hermione are almost at the door but Lockhart stops them and asks them to try and nip the rest of them back into their cage, but in the film, the trio just remain a distance from the door and try to stop them until Hermione immobilises all the Pixies.
 * In the film, Lockhart runs into his office, while in the book, he ran through a door, but it is not specified which door it is.
 * In the novel Hermione freezes several pixies and then sends them back to their cage. In the film, she paralyses all the Pixies and sends none of them back into their cage.
 * Ernie Macmillan's role is diminished to a non-speaking part. The part where he and Hannah Abbott talk in the library about their theory of Harry wanting to attack Justin Finch-Fletchley was cut, but appears on the deleted scenes, however in the Study Hall. Also, Ernie is the one who blames Harry for attacking Justin when he is discovered, petrified, but in the film, Argus Filch finds Harry and wants to expel him. In the book, it was Peeves who found him, and sung his funny song.
 * As with the previous film and all of the following ones, the character of Peeves is omitted completely.
 * During the first Defence Against the Dark Arts lesson, Lockhart refers to the Bandon Banshee as male rather than female.
 * The scene where Lockhart gives out a test is omitted in the film. It is included as a deleted scene on the DVD of the film.

7. Mudbloods and Murmurs

 * In the book, Hermione has never heard the term "Mudblood" before, and Ron later explained the definition to her and Harry. In the film, she is aware of the term and is deeply hurt, even seen trying not to cry, and explains what it means to Harry, though Hagrid defines its origin for Harry and says exactly what Ron says in the book. Ron only responds to it with only two words, as he is in the middle of throwing up slugs.

8. The Deathday Party

 * Nearly Headless Nick's Deathday Party does not appear in the movie, other than in concept art. Because of this, Harry encounters the petrified Mrs Norris on his way back from spending hours of detention with Gilderoy Lockhart instead. Harry also meets Ron and Hermione just before finding Mrs Norris in the film, while in the book they were with Harry the entire time.

9. The Writing on the Wall

 * In the book, Harry, Ron and Hermione are spoken to by the teachers in Gilderoy Lockhart's office. In the film, they are spoken to in the corridor where the attack happened.
 * Mention of Filch being a Squib is omitted. However, very oddly, the term is mentioned in the Danish version of the subtitles; calling him Mr Squib, although with the Danish term.
 * Mention of Ron's detention and the fact that he recognised Tom Riddle's name from an award he received for special services to the school, was cut, but appears on the deleted scenes.
 * In the film, Hermione claims that the writing on the wall is written in blood. The book, however, states that message is simply written in red paint.
 * Because of the scene with Harry first hearing the Basilisk being moved to during his detention session with Gilderoy Lockhart instead of while heading back from the Deathday Party for Nearly-Headless Nick, the teachers' interrogation of Harry, Ron and Hermione was altered:
 * Snape, when talking to Dumbledore about how perhaps the three students simply were present at the wrong place at the wrong time, implied that he viewed Harry in particular as a suspect due to his being absent during dinner, with Lockhart admitting that Harry's absence was actually his own fault, because he had unintentionally had Harry stay behind beyond the intended time period for detention, with Hermione then explaining to Snape that they were absent because they noticed that he was absent and tried to search for him, and was about to mention that he said he heard the Basilisk's voice before trailing off, causing Harry to lie and say that he told her he wasn't hungry.

10. The Rogue Bludger

 * In the book, to borrow the Moste Potente Potions book from the library, which had the recipe for the Polyjuice Potion, Hermione had to get a note from Gilderoy Lockhart (which he signed without looking at) because it was in the restricted section. In the film, the scene was omitted, and the book was in the regular section of the library.
 * In the film, the match takes place in sunlight; in the book, the majority of it takes place in rainy weather.
 * In the book, Draco does not notice the Snitch at all, due to having been insulting Harry at the time and Harry quickly catches the Snitch before Malfoy could realise it, but in the film, he sees it just after Harry does, and just after ducking to prevent being hit by a Bludger, and it leads to both of them chasing after the snitch for a few seconds before Harry catches it first. Also in the film, they chase the Snitch in between the Quidditch Stands.
 * During the match in both book and film, Slytherin had taken the lead of Gryffindor of throwing the Quaffle through the hoops, but they had different scores: In the book, the final score was 60-0, but in the film, the score is 90-30, in which Gryffindor would then receive 150 points because Gryffindor won the match.
 * In the film, while Malfoy was dodging the Bludger, he tilted his broom too low, the tip of his broom hits a beam, causing him to catapult off his broom, and land on the grass, doing a full split. He was still moaning in agonising pain at the Hospital Wing when Madam Pomfrey tells him not to make such a fuss.
 * In a deleted scene from the film Harry tries to avoid being hit by a Bludger by flying in the Slytherin tribune. This does not happen in the book.
 * Lucius Malfoy is seen in the audience observing the Gryffindor-Slytherin Quidditch Match in the film. This is not mentioned in the book.
 * In the book Fred and George attempt to protect Harry from the rogue bludger, and later place it back in its case while restraining it. In the film, Hermione destroys the rogue bludger with Finite Incantatem after the game, effectively damaging a piece of Hogwarts property.
 * In the book, Harry's arm is injured by the Rogue Bludger, before he charges at Malfoy, but after spotting the Snitch, due to a moment of hesitation. In the film it occurs after the added incident in which Malfoy has crashes off his broom. Additionally Hagrid is present when Lockhart removes the bones from Harry's injured arm when attempting to heal the broken bones, whereas he wasn't in the book.
 * In the film Filch supports Slytherin, being seen standing in a crowd of Slytherin spectators, whereas is the books, it is never specified if he takes sides.
 * In the book, when Harry is in the hospital wing following the Quidditch match, Ron, Hermione and Madam Pomfrey are the only people there when he takes the Skele-Gro, the rest of the team come in later and Madam Pomfrey shouts at them to get out. In the film however, the entire team plus Ron and Hermione come with him, and Madam Pomfrey tells them to get out of her way, not to get out of the Hospital Wing.

11. The Duelling Club

 * The scene in which Harry, Ron, and Hermione cause a disturbance in Potions class to steal ingredients from Professor Snape was omitted. This caused a continuity error for where Snape accused Harry of brewing Polyjuice Potion by stealing its ingredients "again." Possible explanations could be that it happened off-screen, or that Snape just came to the conclusion that Harry did it. Also, because Barty Crouch Jr was stealing Snape's ingredients to brew Polyjuice Potion to impersonate Alastor Moody in the fourth film, it is possible that Snape mistakenly thought Harry was stealing the ingredients earlier in his fourth year and was warning him not to do so in what Snape falsely perceived to be a second time.
 * In the Duelling Club scene, Harry and Draco are the only combatants participating, while in the novel, other classmates in their year are shown participating along with them, such as Hermione, Millicent Bulstrode, Ron, Seamus, Neville, and Justin Finch-Fletchley.
 * Also in the Duelling Club sequence, when Harry speaks Parseltongue, in the book, the reader knows what he says immediately, as is the case when Harry speaks with the snake at the zoo in the film version of Philosopher's Stone. In the film, it's only hissing sounds until Harry explains what he said to Ron and Hermione. Other uses of the language later in the film are left untranslated, but most likely are the same as the book's translations. Also the games explains what he says.
 * A line that Snape spoke in the book "Longbottom causes devastation with the simplest spells", was changed to "Weasley's wand causes devastation with the simplest spells" after Professor Lockhart chose Ron and Harry to demonstrate the Disarming Charm (in the book, Snape spoke instead about Neville Longbottom). The film also changed the line "We'll be sending what's left of Finch-Fletchley up to the hospital wing in a matchbox" to "We'll be sending what's left of Potter up to the hospital wing in a matchbox" as Justin Finch-Fletchley did not duel during the scene, either.
 * Also in the Duelling Club scene, Rictusempra was used like a Stunning Spell which caused Malfoy to be thrown up in a back flip. In the book, Rictusempra was described to give its receiver an uncontrollable tickling sensation. Tarantallegra, a jinx used to force someone to dance wildly and involuntarily, was also not used in the film. In addition, attacking with a Serpensortia spell was Malfoy's own choice, whereas in the novel, Snape was the one who gave him that idea. Everte Statum was also not mentioned in the book but was used in the film.
 * In a deleted scene after the Duelling Club, Harry was talking to Hedwig in a mountainous area away from the castle saying "Who am I, Hedwig? What am I?".

12. The Polyjuice Potion

 * In the book, when Harry asks the Sorting Hat whether it put him in the right House, he does it with the hat on his head. In the film, he merely stands before it.
 * The Polyjuice Potion in the book changes colours as the hair is added. In the film, it does not change colours at all.
 * The scene in the Great Hall during the Christmas Feast, Hermione simply says that she got Millicent Bulstrode's hair off her robes. The novel, however, depicts her and Millicent in the Duelling club where Millicent is head-locking Hermione, and she happens to find black hair on her robes.
 * The scene where Harry and Ron hide Crabbe and Goyle in a broom cupboard is omitted (the scene was filmed and included in the deleted scenes section, though). Due to this omission Crabbe and Goyle are dazed and confused when Harry and Ron run past them after their transformation has worn off instead of pounding while still in the cupboard.
 * In the novel, the potion is in one of the stalls and when the trio prepares to drink from their separate glasses, they each go into a different stall and drink. In the film, the potion is in one of the sinks and the trio drink beside that same sink and only Ron and Hermione run into cubicles when they feel they're gonna be sick (not said in the book) while Harry remains at the sink and watches himself transform.
 * In the book, Harry feels his insides start writhing as though he’d just swallowed live snakes—doubled up, then a burning sensation spreads rapidly from his stomach to the very ends of his fingers and toes—next, bringing him gasping to all fours, then comes a horrible melting feeling, as the skin all over his body bubbles like hot wax—and before his eyes, his hands began to grow, the fingers thickened, the nails broadened, the knuckles were bulging like bolts—his shoulders stretched painfully and a prickling on his forehead told him that hair was creeping down toward his eyebrows—his robes ripped as his chest expanded like a barrel bursting its hoops—his feet were agony in shoes four sizes too small. In the film, Harry watches his hands bubbling and then looks into the sink's mirror and watches his face bubbling then turning into Goyle's face.
 * The effects of the Polyjuice Potion differ from book to film. In the film, Harry and Ron's voices don't change when they become Crabbe and Goyle, forcing them to imitate these voices. This was presumably done to avoid confusing the audience because of the change in appearance which would be the standard for the use of the potion in both of the Deathly Hollows films.
 * This causes a continuity error with Barty Crouch Jr's usage of the Polyjuice Potion in as his voice does change when he becomes Moody, though this can be considered as an exception as his identity was kept secret until the end of the film.
 * In the book, Harry's vision changes and he takes his glasses off after using the Polyjuice Potion, but in the film, his vision apparently does not change, and only takes the glasses off when Draco questions Harry (here disguised as Goyle) wearing them.
 * This could also create a continuity error in the film adaptation of the first half of Harry Potter and the Deathly Hallows when Hermione, Ron, and others take the potion to transform into Harry, and Hermione remarks that Harry's eyesight is really bad.
 * During the Slytherin Common Room scene, there are some parts of the book which are omitted from the film, like:
 * Draco showing Goyle/Harry and Crabbe/Ron the Daily Prophet article about Arthur Weasley's inquiry at the Ministry of Magic about having been fined for having an enchanted Muggle car is omitted.
 * Draco does not mention Dumbledore's love of Muggle-borns (but it's obvious that Dumbledore still loved them). Also, due to this omission, Draco does not make the rude mimicking act of Colin Creevey wanting Harry's autograph.
 * There is no mention of Azkaban prison in this scene because Harry did not ask Draco whether he knew if the person who opened the Chamber last time was caught. Instead, it is first mentioned by Hagrid in the scene where Dumbledore and Cornelius Fudge come to Hagrid's hut.
 * In the film, when Draco mentions that "you'd never know" the Weasleys were pure-bloods the way they behave along with an added line that was not mentioned in the book&mdash;"They're an embarrassment to the wizarding world. All of them."&mdash;Ron makes a fist and looks furious, but in the book, Ron's face is just contorted with fury and there is no fist.
 * In the book, Ron and Harry realise they're turning back to normal when Harry sees Ron's hair turning red and his nose lengthening and they run. In the film, they realise when Ron sees Harry's scar reappearing (which didn't happen in the book) and Harry seeing Ron's hair growing red again and whispering "Scar" (Ron) and "Hair" (Harry).
 * There is a scene added in which Draco finds a small package and after shaking it once, asks Goyle/Harry if it's his (Harry's), Harry shakes his head and Draco puts the package in his school robe pocket, then a few seconds before Harry and Ron realise that they're about to turn back to their normal selves, Draco unwraps the package and after Harry's scar reappears and Ron's hair starts turning back to red, Draco is seen to having a small silver object in his hand, but it does not fully appear since it was in Draco's hand. The package was not included in the book.

13. The Very Secret Diary

 * The part where Hermione gets a get well soon card from Gilderoy Lockhart is omitted, but included in the original script.
 * In the book, Professor Binns explains to the class about the Chamber of Secrets during a History of Magic class, but in the film, Minerva McGonagall explains it to the students during a Transfiguration class as Professor Binns is not in the film. In the game, Professor Flitwick explains it during a Charms lesson.
 * The Valentine's Day breakfast in the Great Hall which was arranged by Professor Lockhart is omitted.
 * The scene when Harry gets his Valentine and Draco Malfoy tries to steal Tom Riddle's diary in which Harry disarms him and Percy scolds Harry for using magic in the corridors is omitted.
 * In the book, the ink is scarlet. In the film, the ink is black.
 * In the book, Tom Riddle's diary displays his first and middle names as initials. In the film, Tom Riddle's full first and last names are shown on the diary.
 * In the book, when Harry gets sucked into the diary to 50 years before, he enters through the Headmaster's office where Professor Dippet was reading a letter from Tom Riddle. In the film, he enters below the Grand Staircase where Tom Riddle was standing, shortly before a younger Dumbledore appears to talk to him.
 * In the film, a scene is added in which Harry and Tom Riddle see Myrtle's dead body (unknown to Harry) wrapped up in a sheet with her right arm sticking out and being carried away by several unidentified wizards. This event did not occur in the novel.
 * In the book, Armando Dippet is the one to talks to Tom Riddle about Hogwarts closing. In the film, Dumbledore talks to Tom while Dippet appears only a brief second then turns his back and does not speak to Tom. Although, in the book, after Tom's meeting with Dippet, he finds Dumbledore who asks Tom why he's wandering around late and then tells him to hurry off to bed because it's not safe to roam the corridors these days.
 * In the book, while Harry is in the memory inside the diary and he sees Tom Riddle with Rubeus Hagrid, Tom calls him "Rubeus", but in the film, he calls him Hagrid instead, like everybody else.

14. Cornelius Fudge

 * In the book when McGonagall is cancelling the Gryffindor-Hufflepuff Quidditch match, she is doing this with a large megaphone while out on the field to send the message much to the dismay of Oliver Wood and the audience. In the film however, she simply informs the Gryffindor team just as they were heading out to the field, and Wood is much less aggressive about it than in the book.
 * Ginny's attempt to confide her secret to Ron and Harry is omitted, although a scene where Ginny sees Harry with the diary was initially featured in the script.
 * Almost all foreshadowing hints about Ginny acting strangely or emotionally are omitted. However, in the film, the scene in which McGonagall informs the Gryffindors of the possible closing of the school reveals a close-up of Ginny appearing uneasy as if it's her fault.
 * Possible Explanation: Though Ginny did seem uneasy as if it is her fault, in the book she is "bullied" into taking a dose of Pepperup Potion by Percy. In the film this is omitted, along with the fact that she didn't even notice Harry in the book, while in the film she had said "Mummy, have you seen my jumper?", and Mrs Weasley responded with "Yes dear, it was on the cat." Then, when Ginny sees Harry, he says "Hello" and she turns and hurries off.
 * Penelope Clearwater's role as a Basilisk victim is omitted from the film.
 * The book mentioned that "the crowing of the rooster is fatal to the Basilisk" which led Hagrid's roosters to be killed since the Heir of Slytherin didn't want one near the castle. This was not mentioned in the film, although Hagrid was seen holding one of his dead roosters when bursting into Dumbledore's office in an attempt to defend Harry from being expelled before realising Dumbledore doesn't even think Harry's at fault for what had happened with Mrs Norris, Colin Creevey, and Nearly-Headless Nick. A deleted scene shows Harry finding Hagrid holding the rooster. Hagrid explains his thought about a Blood-Sucking Bugbear, and that he is going to ask Dumbledore for permission to cast a protecting charm.

15. Aragog

 * In the book, after Hagrid mentions that if they were looking for answers, all they'd have to do was follow the spiders, Harry and Ron didn't see any spiders until one day in Herbology when Harry points them out to Ron. They noticed the path the spiders were taking, which was right into the Forbidden Forest, and didn't follow them until everyone had gone to sleep in their dormitory. In the film, right after Hagrid is taken away by the Minister, Harry and Ron see spiders crawling along Hagrid's window and follow them into the Forbidden Forest.
 * In the book, Ron (reluctantly) and Harry looked around for spiders and then when entering the forest, Ron is brave. In the film, Ron is completely scared and reluctant to go into the forest and follow spiders.
 * In the film, Ron asks why they have to follow spiders and why it could not be "Follow the butterflies". This dialogue did not appear in the book.
 * In the book, Harry, Ron and Fang are taken by the spiders to Aragog's lair but in the film they make their own way there. Also, they never see the Ford Anglia before arriving at Aragog's lair; hence their looks of surprise in the film when it crashes through the spiders to rescue them, although a deleted scene shows them finding the car before they meet Aragog.
 * Also, in the deleted scene where Harry and Ron find the Ford Anglia, Harry tells Ron they don't want to lose the trail of spiders, but in the book, they lose the trail and try to find them before being dragged to Aragog's lair.
 * In the film, Mosag, Aragog's mate, is not mentioned.

16. The Chamber of Secrets

 * In the book, when McGonagall and the other teachers volunteer Lockhart to fight the Basilisk, the teachers are collected in the Staffroom with Harry and Ron hiding in the wardrobe. In the film, the teachers are gathered in front of the daubed message on the wall stating Ginny's capture with Harry and Ron hiding behind a corner. Also, in the book the teachers' comments after Lockhart has left them make it clear that they know he is incapable and were simply getting him out of the way. These comments are left out from the film, but it's still highly unlikely the plan was ever genuine and unlike in the book, the second message is seen on-screen in the film.
 * In the book, when Harry and Ron realise that Lockhart is a fraud, they subdue him by performing a Disarming Charm and throwing his wand out of the window. In the film, Lockhart drops his wand in a manner of defeat, when Harry and Ron point theirs at his face.
 * Also, the book has Gilderoy Lockhart citing some specific examples of individuals that he not only stole credit for their deeds from, but also wiped memories from as insurance. The film does not actually list any specific examples of his victims.
 * In the film, just before Harry and Ron jump into the cavernous pit leading to the Chamber of Secrets upon opening it, Moaning Myrtle offers to let Harry share the toilet she lives in should he die in the chamber. She only alludes to this offer in the book after Harry, Ron, Ginny, and a recently-amnesiac Gilderoy Lockhart leave the chamber, where she expressed some implied disappointment in the fact that Harry survived.
 * In the book, it says that the snake who had shed the skin must have been at least twenty feet long. In the movie, Ron remarks that the creature must have been at least sixty feet long.
 * In the book, Harry walks for a longer period through the tunnel to find the Chamber after being separated from Ron and Lockhart, but in the film, the tunnel was only one small room and had the entrance to the Chamber right before Harry, Ron and Lockhart. Although, before they enter the room, there is another passage seen on the opposite side.
 * In the book, the entrance to the Chamber where Ginny was consisted of a solid wall on which two entwined serpents are carved, their eyes set with great, glinting emeralds and when Harry speaks Parseltongue to open the entrance, the serpents part as the wall cracks open and the halves slide smoothly out of sight. In the film, the entrance consisted of a circular door with 7 snakes on it that were on the edge of the door and when Harry speaks Parseltongue to open the entrance, an eighth snake appears from the cylinder bit where the snakes are held and goes all around the door and whenever it approaches each snake's head, the snake's head backs away and allowing the door to be opened.

17. The Heir of Slytherin

 * In the film, Harry, shortly after Riddle rearranged his name to unveil his true identity as Lord Voldemort, explicitly states the latter's the Heir of Slytherin. Harry does not do so in the book, though it was nonetheless made very clear what Riddle/Voldemort's connection to the Heir of Slytherin was.
 * In the film, the Basilisk is seen chasing Harry all around the Chamber of Secrets whereas in the book, Harry's fight against the Basilisk occurs quickly and neatly. In the book, Harry never climbs up the statue nor does he go into the statue.
 * In addition, Tom Riddle's reaction throughout the fight in the film was significantly calmer compared to the book. In the film, outside of yelling "No!" in shock and stating that the Basilisk can still use its other senses (see below), he does not react in any way to the Basilisk missing Harry. In the book, Tom Riddle is repeatedly yelling at the Basilisk to smell Harry when it is repeatedly missing Harry in their fight.
 * The film also has Riddle claiming that Harry Potter's parseltongue abilities are of no use against the Basilisk, as it was specifically trained to only obey him, something that was not in the book (and which conflicted with the revelation later on that Harry Potter was one of Voldemort's horcruxes).
 * In the book, the statue at the end of the Chamber of Secrets is a full body statue of Salazar Slytherin, while in the film it is only a large statue of Slytherin's head and shoulders. Rowling later reveals in Harry Potter Page to Screen: The Complete Filmmaking Journey, that the Chamber is flooded and the rest of the statue below his head is submerged beneath the water (which also explains why the Basilisk was seen emerging from the water near the statue when Harry attempts to wake the nearly-dead Ginny).
 * In the book, after Fawkes had punctured the Basilisk's eyes, Riddle stated that it can still smell Harry. In the film, Riddle stated that it can hear him.
 * In the book, Fawkes uses his tears to heal Harry while Riddle is still alive, but in the film Fawkes does not use his tears to heal Harry until after Riddle's destruction, as such Ginny wakes up and sees the dying Harry.
 * In the book, in the Chamber of Secrets, Harry puts on the Sorting Hat and shouts at it for help. The sword then comes out and hits him on the head, nearly knocking him out. In the film, the sword just all of a sudden materialises in the hat when it's just lying on the ground, and Harry takes it.
 * In the book, pillars hold up the ceiling of the Chamber of Secrets. In the film, there is nothing to hold the ceiling up (although two pairs of pillars do appear in the game version; and in the film, there were two lines of giant statues of snakes' heads where the pillars were in the book).
 * In the book, Harry Potter only destroyed the diary with the basilisk fang after he was healed by Fawkes. In the film adaptation, Harry destroyed the diary with the fang before he was healed.
 * In addition, the book only mentioned that Riddle's memory writhed and then faded away after the diary was destroyed, while in the film, it was shown that Riddle's memory's chest cavity ripped open with light, then destroying his eyes and causing damage to his face, before eventually causing gaping holes throughout his body upon exploding.
 * Lastly, Harry Potter only stabbed the diary once in the book, while in the film, he stabbed the diary three times, two being in two different sections of the book, and the last from the outside.
 * The film has Ginny reacting in a significantly calmer manner when awakening shortly after Tom Riddle's memory was destroyed than in the book. In the latter, in addition to admitting her unwilling role in the disaster, Ginny clearly was breaking down from the entire ordeal. Similarly, because of the switching around of Fawkes healing Harry and the destruction of the diary (see above), Ginny also notices that Harry was injured, something that was not the case in the book.
 * In the novel, when Harry and Ginny find Ron and Lockhart, Lockhart (having lost his memory) says 'Hello', that the chamber is an odd sort of place and asks if the three live there to which Ron answers 'No'. In the film, this occurs before Harry enters the Chamber and finds Ginny and Lockhart having just caused the tunnel to collapse; He says 'Hello', asks Ron who he is to which he replies "Um... Ron Weasley." and Lockhart responds "Really? And who am I?" then Ron says to Harry through the gap hole of the rocks that Lockhart's Memory Charm backfired and that he hasn't got a clue who he is. Then Lockhart picks up a stone, gives it a short throw then asks Ron if he lives in the Chamber (and also gives the stone to Ron) to which Ron replies "No." and Lockhart replies "Really?" and then Ron does something he never did in the book: He hits the stone on the top of the left side of Lockhart's head and he falls back down (presumably unconscious).
 * The departure from the Chamber is depicted differently in the film and the book by the end of the characters' journey with Fawkes. The books states that the journey ends in Moaning Myrtle's bathroom, where the entrance seals shut again, and they head to McGonagall's office. The film shows that the characters are carried by Fawkes to a cave entrance in a cliff wherein a full moon gleams and they land onto the grounds of Hogwarts, then head to Dumbledore's office. The landing at the Hogwarts grounds and heading to the headmaster's office is done offscreen.

18. Dobby's Reward

 * In the film, when Lucius arrives at Dumbledore's office and Harry notices Dobby, he is shown realising that Dobby's masters were the Malfoys and thus explained why he was hesitant to reveal anything directly or his self-inflicted punishments, with Lucius then giving a veiled threat to the house elf in response. This did not happen in the book (largely because Dobby had already been speculated to be part of the Malfoy family much earlier in the book).
 * In the book, Harry's conversation with Dumbledore after the defeat of the basilisk is set in McGonagall's office, and Arthur, Molly, and McGonagall are present at the start of the scene. In the film, the scene is set in Dumbledore's office instead, and Arthur, Molly, and McGonagall do not appear.
 * In the book, Harry accused Lucius of deliberately supplying the diary to Ginny Weasley at Diagon Alley while they were still in Dumbledore's office and Lucius is meeting with Dumbledore, with Dumbledore also giving a veiled threat to Lucius in response to this as well as his forcing the board of directors to fire Dumbledore. In the film, Harry's accusation occurs after Lucius leaves, and Dumbledore, while still implicitly warning Lucius about his actions with the diary, is not notified by Harry about Lucius's action with the diary.
 * In the film, Lucius Malfoy's sarcastic statement about Harry and Harry's response was improv from the actors.
 * In the book, to free Dobby, Harry puts the diary in his sock and had Lucius Malfoy throw it so Dobby would catch it after he removed the diary, but in the film Harry puts his sock in the diary and had Lucius give the diary with the sock to Dobby unknowingly instead.
 * In the book, just after Dobby was freed, Malfoy raises his wand threateningly at Harry, before Dobby tells him to leave. In the film, it sounds like Lucius Malfoy starts saying "Avada Kedavra" before Dobby blasts him backwards across the hall (the spell was the result of an ad-lib by Jason Isaacs).
 * In the book, Lucius Malfoy says to Harry, "Someday you'll meet the same sticky end as your parents. They were meddlesome fools too." In the film, he said, "Your parents were meddlesome fools, too. Mark my words, Potter - one day soon, you're going to meet the same, sticky end."
 * During the dinner scene, the scene where Gryffindor wins the House cup again is cut, though it is nonetheless implied.
 * Hermione originally hugged both Harry and Ron in the book upon revealing that she had been cured. In the film, she only hugs Harry, and just gives a hesitant handshake to Ron (note, this was the result of Emma Watson being hesitant to hug both Daniel Radcliffe and Rupert Grint in public view, with her hugging Radcliffe during filming having to be frozen for a few seconds to get the desired effect due to Watson breaking the hug too quickly). This also unintentionally foreshadowed her and Ron's hesitant blossoming feelings for each other in the succeeding films.
 * In addition, Hagrid's arrival has him apologising for his lateness, explaining his release from Azkaban was delayed due to the letter requesting his release getting lost, and proceeding to blame a bird named Errol for it getting lost, causing Ron to give a slightly embarrassed look. This was not present in the book.

1. Owl Post

 * The film starts with Harry performing the "Lumos Maxima" Spell, well aware of the Restrictions of Underage Wizards and did not receive any warnings; every time he does it, Uncle Vernon would come to see what was happening and Harry would hide under the covers. In the book, Harry uses a simple torch. Lumos Maxima is later used in the sixth film.
 * Harry does not receive birthday presents from his friends and Harry does not find out about the Weasley's visit to Egypt until he gets to the Leaky Cauldron.
 * The film does not mention about Ron receiving a new wand to replace his old broken one. However, Ron actually has a new wand, since there is no spello-tape on his wand and no malfunctions happen.

2. Aunt Marge's Big Mistake

 * In the book, at the dinner party, Aunt Marge allows Ripper to drink tea off of a saucer. In the film, she allows him a drink of brandy from her glass.
 * In the book, Aunt Marge stays for a couple of nights before she gets blown up. The film makes it seem she blows up the same day she visits.
 * In the book, Harry sat at the table with Aunt Marge and the Dursleys, but in the film, he is just busy at the kitchen counter serving the Dursleys and Aunt Marge.
 * Also in the book, Marge only floats up to the ceiling, while in the film she uncontrollably floats out of the house, later to be found circling a chimney in Sheffield.

3. The Knight Bus

 * In the book, Harry pretends to be Neville Longbottom while on the Knight Bus, running from the Ministry of Magic. In the film, Harry doesn't pretend to be Neville; however, his identity is still kept secret.
 * The film makers added Shrunken heads that have the ability to talk, probably to add humour. So far these creatures have been unique to this film only. In an interview on the DVD release, J.K. Rowling said the addition of the shrunken heads had her full support, and she only wished she'd thought of them herself.
 * Harry asking Cornelius Fudge to sign his Hogsmeade permission slip is taken out.
 * In the book, Harry still has only two weeks of vacation remaining left before returning to Hogwarts, following the incident of blowing up Aunt Marge as mentioned by Cornelius Fudge; But in the film, Harry returns to Hogwarts the next day after having arrived at the Leaky Cauldron.
 * In the book, Harry reunites with Hedwig in his room at the Leaky Cauldron with Tom telling Harry that Hedwig arrived five minutes after he did; But in the film, Harry reunites with Hedwig withTom telling Harry that Hedwig arrived five minutes before Harry did.

4. The Leaky Cauldron

 * There are no scenes in Diagon Alley, in the film, resulting in Harry reuniting with Ron and Hermione in the Leaky Cauldron lounge.

5. The Dementor

 * During the train ride, Malfoy, Ginny and Neville do not come into the trio's compartment.
 * The Hogwarts choir doesn't exist in the book and the director only added it for the film, however, it was later mentioned in the sixth film as well (in the scene in which Professor Flitwick uses "emergency choir practice" as an excuse to escape a conversation with Professor Slughorn).
 * McGonagall doesn't call away Harry and Hermione prior to the feast.

6. Talons and Tea Leaves

 * Professor McGonagall's Transfiguration classes never happen at any point in the film, and as such, she never performs her Animagus ability or tells the students not to listen to what Trelawney says. Professor Snape's Potions classes also never happen.
 * When the Gryffindors and Slytherins go to their first Care of Magical Creatures lesson in the book they visit the Hogwarts Hippogriff Herd, but in the film Buckbeak appears to be the sole hippogriff at Hogwarts.
 * The film has scenes that suggest a growing romance between Ron and Hermione. During their first Care of Magical Creatures class, Hermione grasps Ron's hand when Harry goes up to Buckbeak, which surprises him. Later on in Hogsmeade, they stare at the Shrieking Shack with Ron confusing Hermione's dialogue when she spoke of "getting closer" to the Shack. Then after Buckbeak's apparent execution, Hermione starts crying and hugs Ron.
 * When Harry rides on Buckbeak in the film, they fly all the way to the Hogwarts lake; in the book, they fly only once around the paddock in the Forbidden Forest.
 * In the book, Harry doesn't quite enjoy his first ride on Buckbeak, and it's made clear between hippogriffs and broomsticks which one he prefers. But in the film, during his first ride on Buckbeak, Harry is fascinated by the ride and enjoying it a lot as they fly over the Black Lake, raising his arms and shouting in triumph. The film portrayal also depicts a much longer ride, with Buckbeak achieving a sort of smooth, idyllic glide not described in the novel.
 * In the novel, Malfoy is bleeding from his arm after Buckbeak attacks him which falls on the grass. In the film, Malfoy is not bleeding and only a piece of white from Buckbeak's scratch can be seen, although it's probably just Malfoy's shirt as it seems Buckbeak slashed his robe sleeve open.
 * The part of Bem was created solely for the film, he explains to Seamus Finnigan what the Grim is and also expresses his concern over the Dementors effectiveness at catching Sirius.

7. The Boggart in the Wardrobe

 * In the book, Harry, Ron and Hermione make their way to Defence Against the Dark Arts class, when Hermione disappears but then reappears a few feet behind them. In the film, Harry and Ron are already in the classroom when Hermione appears during the lesson.
 * In the book, Parvati Patil's boggart is a mummy; in the film, it is a giant snake.
 * In the book, the Boggart which had transformed into a spider to scare Ron, loses its legs when Ron casts the spell on it and rolls over to Harry, where Lupin prevents it from transforming, while in the film Ron conjures some roller blades to appear on the spider's legs, after which Parvati faced it, and it transformed into a massive serpent, but was again countered, after which it was faced by Harry, upon which it transformed into a Dementor, upon which Lupin stopped it and sealed it back into the cupboard.

8. Flight of the Fat Lady

 * While the book has Peeves describe Sirius Black's attack on the Fat Lady's portrait after learning about this from her when he saw her in a portrait on the fourth floor, in the film it was the Fat Lady herself that described the attack from a nearby portrait.
 * In the book, while Harry cannot go to Hogsmeade and stays with Lupin, they spend their time in his office and Harry sees a Grindylow which Lupin was taking delivery of for their next lesson, while in the film, they are talking on the Wooden Bridge. This difference creates a continuity error in the seventh film when Lupin interrogates Harry after the Battle of the Seven Potters holding his wand to Harry's face and asking him 'what creature sat in the corner the first time Harry Potter visited my office in Hogwarts.' (although Harry could have visited him in his office off screen, before the two of them went for a walk on the Wooden Bridge)

9. Grim Defeat

 * Sir Cadogan never appears, and as such his role of replacing the Fat Lady as Gryffindor's portrait is only shown as a deleted scene.
 * In the novel, when Snape substitutes for Lupin in Defence Against the Dark Arts, Harry is 10 minutes late and Snape takes 10 points then another 5 when Harry is told to sit down, but continuously asks where Lupin is. Hermione then says that they had done Boggarts, Red Caps, Kappas and Grindylows and that they're about to start something else before being cut off by Snape and a moment later when he announces that they will start a lesson about werewolves, but Hermione tells him that they are not meant to start that topic yet and that they're due to start Hinkypunks. Snape then asks the class who can tell him how to distinguish between the werewolf and the true wolf, Snape immediately criticises Hermione and deducts an extra 5 points from Gryffindor then Ron shouts at Snape for taking points when Hermione knows the answer and he gives Ron detention. In the film, this is all different in some ways and this scene also has a few moments that did not occur in the book:
 * Harry is already in class before Snape enters, so Harry is not at all late. This also omits Snape taking the first 15 points from Gryffindor. However, Harry asks only once in the film where Lupin is and Snape replies "That's not really your concern, is it, Potter? Suffice it to say that your professor finds himself incapable of teaching at the present time."
 * Hermione tells Snape that they had just began learning about Red Caps and Hinkypunks and are not meant to start werewolves for weeks before Snape tells her to be quiet. Also, Hermione learns Snape will be teaching werewolves after he does an action that does not happen in the book: He sees Ron turning his pages one-by-one before Snape makes a movement with his wand and the book turns to page 394 (as Snape requested) and Ron says "Werewolves"?.
 * Another thing that occurs in this scene that didn't happen in the book is the class having a projector which is why Snape, when he enters, magically closes all the windows shut.
 * Snape asks the class who can tell him the difference between an Animagus and a werewolf.
 * Ron remains quiet and calm and does not get detention when Snape takes 5 points from Gryffindor when accusing Hermione of being an insufferable know-it-all.
 * In stark contrast to the previous films, in which Quidditch always had a notable role, the majority of the Quidditch season was written out, aside from the first match.
 * As such, the part of Harry winning the Quidditch Cup was omitted.
 * In the book the rain during the Hufflepuff Quidditch match makes it difficult for Harry to see until Hermione casts Impervius on his glasses, In the film, the Quidditch players wear goggles.
 * Also in the book, Harry falls off his broom and Cedric catches the Snitch. In the film, he is struck by lightning and then Harry falls off his broom, leaving the Snitch apparently uncaught. Also in the film, Katie Bell crashes after her broom catches fire which never occurred in the book.

10. The Marauder's Map

 * The origins of the Marauder's Map are not revealed in the film. The whole storyline of the Marauders is left out. Potential continuity errors are avoided in later films when Voldemort refers to Pettigrew as "Wormtail" in the dream Harry witnesses (in Goblet of Fire) and "Mad-Eye" Moody refers to Sirius as "Padfoot" in front of Harry (in Order of the Phoenix), which allows for Harry to know their nicknames. In the film Sirius shows knowledge of the map stating that the map never lies.
 * In the film, Harry's two visits to Hogsmeade are combined into a single trip.
 * In the book Ron and Hermione were with Harry when he eavesdropped on Fudge's conversation with staff and Rosmerta. In the film Harry was alone as the Inn forbade under-age wizards from entering the pub that day. Also in the film Harry snuck in using his Invisibility Cloak, while in the book he hid underneath Ron and Hermione's table as he did not bring the cloak during his first visit to Hogsmeade.
 * In the film, this conversation is taken to a private room, with only Harry, Rosmerta, McGonagall, and Fudge present.
 * In the film, Harry's reaction to the truth is limited to a single scene where he angrily swears he would kill Black. In the book, this was more drawn out where Harry was both angry and depressed for days with nightmares over this fact and that the people who knew the truth did not bother to tell him.

11. The Firebolt

 * In the book, Harry received his Firebolt for Christmas right after his Nimbus 2000 was destroyed. Eventually, Sirius Black revealed he had sent the broom. In the film, Harry receives the Firebolt at the end of the film, and although there was no note, Hermione shows Harry that one of Buckbeak's feathers came with it.
 * In addition, the book had Professor McGonagall confiscating the Firebolt shortly after Harry received it to check for jinxes after Hermione notified her of it, under suspicions that Sirius Black sent it, and taking months before Harry was allowed to use the Firebolt. All of this was omitted from the film due to the switching of when the Firebolt was given and as such Harry does not get into an argument with Hermione.
 * In the book, Ron and Hermione get in a huge argument because of the problems with their pets; in the film most of this is omitted, except for some of Ron's initial arguments with Hermione which didn't go as far as the book.
 * Neither Hermione or Ron attempt to help Hagrid prepare for Buckbeak's trial in the film.

12. The Patronus

 * In the book, during his first anti-dementor lesson, Harry tries to ward off the dementor twice unsuccessfully before succeeding. But in the film, he only tries once unsuccessfully before succeeding. Also, Harry's memory in the book that works is the memory of how happy he was that he would be leaving the Dursleys. In the film, he uses a made-up memory of his parents.

13. Gryffindor Versus Ravenclaw

 * In the film, the part where Sirius tries to kill Wormtail disguised as a rat in the middle of the night with a knife scaring Ron and slashing his bed curtains is omitted. However, the scene where McGonagall is in the Common Room and Ron tells about what happened is included in a deleted scene.
 * Due to Quidditch being mostly written out, Cho Chang does not appear until the next film.

14. Snape's Grudge

 * Harry throws snowballs at Draco and his cronies while under the Invisibility Cloak in the outskirts of Hogsmeade. In the novel, he throws mud-balls. The scene is also extended, with Harry also debagging Crabbe and kicking his backside, pulling Pike's hat over his eyes and swinging him around by his scarf, and dragging Malfoy away by his feet. Omitted from the film is the hood of the cloak falling off Harry's head causing Malfoy to learn of Harry's unauthorised visit, so no one (except Ron, Hermione, Fred and George) knows of Harry's illegal visiting.
 * Hermione is also watching this with Ron in the film. In the book Harry and Ron had not reconciled their problems with Hermione yet, so she was elsewhere (Harry had ceased speaking with Hermione because she had reported the Firebolt to McGonagall, and Ron was also no longer on speaking terms with Hermione because Crookshanks has been attacking Scabbers non-stop).
 * In the novel, while trying to make the Marauder's Map "reveal its secrets," Snape tries once and fails. He then tries again with different words and it fails. He tries once more, again with different words, and it finally insults him. In the film, he only tries once and it insults him.
 * In the film, the "Snape's Grudge" scene happens at night when Snape catches Harry in the hallway after he saw Pettigrew's name one night on the Marauder's map and went to find him. In the book, Snape catches Harry in the hall right after he climbed up the One-Eyed Witch's hump after being seen by Malfoy in Hogsmeade. Both versions of the "Snape's Grudge" scene end with Lupin taking the map.
 * Due to the differing circumstances to how Harry was caught in the film, Ron is absent from this scene. In the book, Ron came and claimed the map was from Zonko's Joke Shop to help cover for Harry and was also present when Lupin lectured Harry about the map after Snape left.
 * In the book, when Professor Snape is insulted by the Marauder's Map, each Marauder says something different to Professor Snape, with Lupin saying the bit about Snape minding his own business. In the movie, however, that is all that the map says.

15. The Quidditch Final

 * In the novel, Hermione slaps Malfoy and he reacts passively. In the film, this is slightly extended. Instead, Hermione first draws her wand on Malfoy, and then punches him in the face, in both situations he acts cowardly.
 * In the books, Hermione was walking behind Harry and Ron on their way to Charms, but when they get to the class she is gone, and they don't know where is until later that day when they find her sleeping on the Arithmancy book in the Gryffindor Tower. None of this happens in the film.

16. Professor Trelwaney's Prediction

 * In the film, after Hermione storms out of the Divination lesson from being insulted by Trelawney, on her way out, she knocks a Crystal ball off the table and it rolls down the Divination Stairwell. Harry notices it on his way out and decides to take it back to the classroom. He then finds Trelawney in a trance and it is here where she tells him a prophecy. In the book her trance takes place during Harry's Exam.
 * In the book, while the trio are on their way to Hagrid's hut when Buckbeak's execution is to take place, they bring Harry's Invisibility Cloak with them, but in the film, they do not bring the cloak at all.
 * In the novel, during the trio's visit to Hagrid, they follow him out in to his back garden where he comforts Buckbeak and says "It's okay, Beaky." This is omitted from the film, as Hagrid doesn't have a garden and Buckbeak is laying right outside the front of Hagrid's hut.
 * In the film, in Hagrid's hut a jar of yellow powder breaks which appears to have been thrown by a kind of rock fossil and then another one hits Harry on the back of the head. This causes Harry to turn and show Hagrid that Dumbledore, Fudge and Macnair are coming. In the novel, Hagrid just sees the party coming through his window and tells the trio to leave and there is no vase broken.
 * The feeble, elderly member from the Committee for the Disposal of Dangerous Creature never appears.

17. Cat, Rat and Dog

 * In the film, after Buckbeak’s apparent execution, Hermione starts crying and hugs Ron while Harry comforts her. This never happens in the book.
 * Crookshanks never recognises Sirius as an Animagus in the film.
 * In the book, Ron is generally depicted as being brave and heroic under stress while Hermione was depicted as being nervous, terrified/frightened. In the movie, Ron's bravery was transferred to Hermione and Hermione's nervousness/terror was transferred to Ron.
 * In the movie, Ron saw Sirius/Padfoot appear and pointed the dog out to Harry and Hermione in a quivering, frightened tone of voice. No such bit appeared in the book.
 * In the book, Sirius (in Animagus form) had grabbed Ron by the arm and that Ron's leg was broken when he tried to use one of the Whomping Willow's roots to hold them in place to avoid being dragged off only for the pressure to break his leg. This was changed to Ron being grabbed by the leg in the film likely for being too graphic.
 * In the novel, when Hermione and Harry find Ron in the Shrieking Shack, Sirius disarms Harry and Hermione with Ron's wand and catches their wands, but in the film, he does not as he does not have Ron's wand. However, Harry does get disarmed by Lupin the moment he enters the room in both the book and film, while in the film Hermione's wand is in her pocket, as seen when Harry uses it to blast Snape backwards, but in the novel, Lupin blasts Harry's wand away and two other wands that Hermione was holding and Lupin catches them all deftly. Also, in the film, when Lupin disarms Harry, the latter's wand disappears near the staircase. Ron is not disarmed in the film, although like Hermione, he does not consider using his wand.
 * The following text appears in the book, after Harry and Hermione find Ron and Sirius in the Shrieking Shack: Ron spoke to Black. "If you want to kill Harry, you'll have to kill us too!" he said fiercely, though the effort of standing upright was draining him of more colour, and he swayed slightly as he spoke. In the movie, the line was spoken by Hermione while Ron remained in the corner and did not say or do anything.
 * This quote is also said in the book, after Lupin enters and greets Sirius as an old friend: "I trusted you, and all this time you've been his friend!"; It was shouted at Lupin by Harry, but in the film, it is Hermione who shouts this at Lupin when she thinks both he and Sirius are wanting to kill Harry when Sirius says "Let's kill him!" (although he was actually referring to Peter Pettigrew). She also first shouts "NO!!" before saying Harry's line from the novel.
 * In the film, after seeing Pettigrew's name on the map, Harry says this to Lupin. In the book, Harry never saw Pettigrew's name on it, and Lupin was the one who saw Pettigrew's name after acquiring the map and using it on the same day as Buckbeak's execution, since he knew Harry, Ron, and Hermione would visit Hagrid that day. These events are what caused Lupin to believe that Sirius is innocent.

18. Moony, Wormtail, Padfoot and Prongs

 * The story of Lupin's connection to the Shrieking Shack and Whomping Willow is omitted.
 * In the novel, Snape appears in the Shrieking Shack after pulling off the Invisibility Cloak, but in the film, as the trio didn't bring the cloak with them, Snape appears visible and is seen when he disarms Sirius.
 * Also, in the film, Snape disarms Sirius with Lupin's wand since Lupin passed it to him when Sirius was so wanting to kill Pettigrew. In the novel, Lupin never gave his wand to Sirius, so Snape never disarms the latter.

19. The Servant of Lord Voldemort

 * As the identities of the Marauders are not revealed until the fourth and fifth films, it causes a bit of confusion as to why Snape has such a hatred towards Sirius and Lupin in the third for those who have not read the books. In the novel, Snape is as eager to hand over Lupin to the dementors as well as Sirius, despite the fact that there is not any evidence supporting Snape's claim that Lupin was helping Sirius into the castle, which he was not.
 * In the film, Lupin pleads with Snape while Sirius continues to insult him. Snape is more calm, confronting the two, as opposed to the book, where he seems to be angry and even more reluctant to listen, as he bounds and gags Lupin, threatens Hermione with suspension and states that Harry deserved to be killed by Sirius.
 * In the book, Harry, Ron, and Hermione all try and disarm Snape at the same time, causing him to hit against the wall and go unconscious. In the film, it is only Harry who does this, as seen when he sneakily pulls Hermione's wand from her pocket, while Ron holds onto her sleeve to keep her hand still, as Harry removes it. Still, both Ron and Hermione are shocked Harry did this, as Snape is a teacher.
 * In the book, Ron hesitates before giving Scabbers, or rather Peter to Lupin. In the film, it is Sirius who takes Peter from Ron, and he does it by force, instead of Ron giving Peter to him freely.
 * In the book, it takes a while for Peter to confess to betraying Lily and James Potter, while in the film, he confesses almost immediately, as the film versions always cut to the chase.

20. The Dementor's Kiss

 * In the books, a transformed werewolf is described as looking almost like a true wolf except for a few subtle differences like the shape of the snout and tail and the eyes. However in the film a transformed werewolf looks more like the anthropomorphic versions from other werewolf films.
 * In the book, Snape had been unconscious because of the spell cast by Hermione, Ron, and Harry and had to be suspended in mid-air by magic to be brought out of the Shrieking Shack. He was not there to protect Hermione, Ron, and Harry when Lupin transformed into a werewolf, but in the film, Snape was left behind, but suddenly regained consciousness to protect Harry, Ron, and Hermione from Lupin. In the book Snape regains consciousness only after Sirius, Hermione and Harry become unconscious because of the Dementors.
 * In the film, while Sirius and Lupin (both transformed) fight, Harry runs up and throws a stone at Lupin, hitting him on the back of the head which causes Lupin to try and attack Harry, until the sound a female wolf (sounding like Hermione's voice) stops Lupin and then runs away. Harry never threw anything at the transformed Lupin in the book.
 * In the book, Hermione is with Harry and Sirius when they are attacked by the Dementors. In the film, she attempts to run after him, but is stopped by Snape, forcing her to stay behind with Ron.
 * In the book, Ron is obviously stunned unconscious by Peter Pettigrew with Lupin's wand, but in the film, Ron is not stunned and remains conscious the whole time.

21. Hermione's Secret

 * In the film, Dumbledore instantly believes the trio, like in the book and gives them rules how to rescue Sirius. When Dumbledore is telling them this, however, he absent-mindedly taps Ron's bandaged leg which does not happen in the book.
 * In the book, Dumbledore tells Harry and Hermione that Sirius is locked up in Professor Flitwick's office in the West Tower, thirteenth window from the right of the tower, but in the film, Dumbledore tells Harry and Hermione that Sirius is locked up in the topmost cell of the Dark Tower.
 * In the book, when Harry and Hermione go back in time, the whole view of the hospital wing disappears and different colours and shapes blur around them until they soon land in the deserted Entrance Hall, but in the film, when Harry and Hermione go back in time, they remain standing in the hospital wing while Harry watches themselves as well as others who were in the hospital wing since the previous three hours doing everything backwards until the whole thing stops. This means that the view does not disappear and no different colours or shapes appear around Harry and Hermione in the film.
 * In the film, when Harry and Hermione go back in time, Hermione throws 2 ammonites fossils at both Hagrid's pot (because that had happened) and at Harry to get his attention, so he can see Fudge and Macnair coming to Hagrid's hut. Hermione later howls like a wolf to call Lupin away from fighting Padfoot, in turn causing him to come after them instead, at which point they are rescued by Buckbeak. In the novel, neither of these two events occur.
 * Hermione throwing ammonites fossils is obvious of not occurring in the novel, especially since neither the pot or Harry got hit by any of the fossils.
 * In the film, Hermione is with Harry when he saves himself, and Sirius from the Dementors, instead of with Buckbeak at Hagrid's cabin.
 * In addition in the book, when Harry is about to break out into the open, he points out to a protesting Hermione that they need to get out into the open, not to interfere, but to evade the then-incoming (and recently-transformed) Professor Lupin. This was obviously changed in the film.
 * In the book, Harry figured out that he was one that cast the Patronus that saved their past selves before using it. In the film, as Hermione was with him, she convinces Harry that no one is coming to save them leading Harry to cast the Patronus and realising the truth afterwards.
 * In the book Hermione rescues Sirius Black with "Alohomora," but in the film, she uses "Bombarda," a spell made up for the films. In the French adaptation of the movie, the spell "Alohomora" is used, instead of Bombarda.

22. Owl Post Again

 * In the film, when Harry and Hermione go back to the hospital wing after saving Sirius Black and Buckbeak, Ron is already awake and asks how he and Hermione got outside the wing, when they were right in front of him. In the novel, Ron is still sleeping when Harry and Hermione get back.
 * In the novel, when Harry arrives in Lupin's office, Lupin tells him about his resignation, that he resigned because Snape told the Slytherins about Lupin being a werewolf until Dumbledore comes in. When Dumbledore is there, they discuss about Harry feeling bad for not letting Lupin and Black kill Pettigrew, realising he would help Voldemort return from Trelawney's prophecy. Dumbledore reminds Harry that he saved Black, an innocent man, from a terrible fate, that Pettigrew owes a life debt to Harry for saving him, which Dumbledore is sure will prove useful later on. Dumbledore also mentions that Harry has some of his father's qualities, which is why his Patronus took the form of Prongs (a stag). In the film, it is Lupin tells Harry all this. Also:
 * Snape is not identified as being the one revealing the secret of Lupin’s condition.
 * There is no mention why Harry’s Patronus is a stag, though it was included in the original script.
 * Harry appears to say that he feels sorry for not letting Sirius and Lupin kill Pettigrew although in a very different way (if this is true): “None of it made any difference. Pettigrew escaped.”
 * There is no talk about Trelawney going strange, when she was actually making the second prophecy.
 * The part of Ron receiving the owl Pigwidgeon from Sirius Black to replace Scabbers has been omitted. This caused a continuity error with the following films where Ron was seen with him, without any explanation on how he got an owl, though of course he could have gotten an owl by other means and as Pigwidgeon is very small he would likely be a cheap owl for Ron to get.
 * The letter addressed to Harry that Sirius sent with Pigwidgeon which gave him visitation rights to enter Hogsmeade was omitted. This caused some continuity errors in the following films of Harry being able to enter Hogsmeade freely.
 * The part where Harry meets his Uncle Vernon on the platform in King's Cross station is omitted in which he tells his uncle that he has a godfather, who has escaped from wizard prison.
 * Many students appear in the film in classes with Harry and other named parts, more than originally sorted into each house with over ten Gryffindors in one scene alone, despite the fact Harry's year has only eight Gryffindors.

1. The Other Minister

 * In the Book, the Diagon Alley attack is merely mentioned, and the Death Eaters were said to have kidnapped both Ollivander and Florean Fortescue. The attack is actually shown in the film, but only Ollivander is seen captured. PotterCast later revealed that Florean was murdered.
 * In the book, the Brockdale Bridge was said to have been destroyed by the Death Eaters, with around fifty Muggles being killed. In the film, it is the Millennium Bridge that the Death Eaters are shown to have destroyed, though all of the Muggles escape before it collapses.
 * Much of the first chapter has been omitted. This includes Cornelius Fudge discussing the murders, hurricanes, and bridge collapses that have been going on to the Muggle Prime Minister, as well as the former's resignation as Minister of Magic, and Rufus Scrimgeour introducing himself to the latter. However, there is still a minor reference in the Daily Prophet at the beginning of the film that mentions there is a new Minister for Magic. The film instead begins with Bellatrix's final line ("I killed Sirius Black!") from the previous film echoing as Harry is seen standing in front of a mob of reporters, with their cameras flashing, when Dumbledore begins to lead Harry away. The scene then cuts to the bridge attack.
 * As the scene with Fudge and the Muggle Prime Minister is not featured in the film, after the kidnapping is shown, the film cuts to Harry reading a copy of the Daily Prophet in a Muggle café located along Surbiton station, then leaves it on the table when he sees Professor Dumbledore outside. Also, the Muggle waitress at the cafe flirts with Harry and asks about the newspaper he reads in the film. This scene is entirely unique to the film, and Harry does not appear until later in the book.

2. Spinner’s End

 * The Spinner's End film location is inconsistent with the book. The mill referred to in the text is not a watermill or windmill, but a nineteenth-century textiles factory in a northern industrial town in the UK, most likely in Lancashire or West Yorkshire. The text references the mill chimneys (now disused) and rows of nearby houses. Terraced houses as shown in the film are typical of late nineteenth century mill-workers houses in industrial Britain.
 * When Narcissa and Bellatrix go to meet Snape, Bellatrix does not show the intense loathing for Snape that she does in the book and does not press him to answer questions about his allegiances. Narcissa does not seem as grief stricken as one might expect—she does, however, have tears in her eyes—and is not the one who suggests the Unbreakable Vow. Her hair is a mix of blonde and dark brunette stripes, rather than being completely flaxen blonde. Snape immediately agrees to the vow in the book, while in the film, he seems rather hesitant to do so, suggesting that he was merely acting on orders, as would be revealed in the final book and film.
 * In the book, Bellatrix and Narcissa are met at the door by Snape, who then brings them to the parlour. Peter Pettigrew is then called in to bring them drinks. He does so, and then hurries upstairs to listen by a door, which Snape says is a new habit he has taken up. In the film, it is Peter who greets Narcissa and Bellatrix, and shows them to the parlour, where Snape is waiting. Snape then uses his wand to slam the door shut, barring Pettigrew from the room. Snape already has drinks out in the film.
 * The scene where Bellatrix kills a fox is omitted from the film.
 * The scene is also in a different place from the book. In the book, this scene takes place directly after Fudge talks with the Prime Minister. Whereas in the film, the scene takes places after Harry has met Horace Slughorn and has travelled back to the Burrow and has reunited with Ron, Hermione, and the other Weasleys.

3. Will and Won't

 * The way Harry meets up with Dumbledore is changed. In the book, Dumbledore comes for Harry at Privet Drive as he had pre-arranged in a letter, having a cup of tea and conversing with the Dursleys (who are absent from the film) before heading off with Harry. In the film, Harry is in a station cafe when he spots a flickering light in a distant part of the station. As a train whizzes past, Dumbledore appears on the platform across the tracks. Harry then heads over to the other platform to meet him.
 * In the film, Harry is never mentioned to have inherited Grimmauld Place or Kreacher after Sirius Black's death, as he did in the book.
 * House-elf Kreacher and the Hippogriff Buckbeak are omitted from the film, and there is no mention of Hagrid getting Buckbeak back.
 * There is no sign of any pamphlet showing the Safety measures issued by the Ministry.

4. Horace Slughorn

 * In the film, since 4 Privet Drive is omitted, Harry having his owl Hedwig and trunk transported is said differently. In the book, while at the Dursley's house, Harry is carrying the owl cage and his trunk out, when Dumbledore tells him they don't want to be bothered with the luggage, and says he will send them to the Burrow. Dumbledore then waves his wand to make the owl and trunk vanish, and he and Harry set out to collect Slughorn. In the film, the matter of Harry's owl and trunk is not brought up until after the meeting with Slughorn, when Dumbledore tells Harry he will not be returning to Little Whinging. Harry asks about his owl and trunk, to which Dumbledore states that both are waiting for him at his next destination (the Burrow).
 * The entire village of Budleigh Babberton is recreated from the book, including the old war memorial. There is a pub called Babberton Arms in the background.
 * In the book, Dumbledore tells Harry to take his left arm while on Privet Drive, as his wand arm was a little fragile, which Harry obliges and they apparate to Budleigh Babberton. There, as the two are talking, Dumbledore mutters "ouch" and points to his right arm. Harry then asks what happened to that hand, to which Dumbledore says that he has no time to explain it, but the tale is thrilling and he wants to do it justice. In the film, Harry meets Dumbledore on a train platform, and Dumbledore shows his right hand after Harry mentions how he enjoys riding on trains. Harry is a little startled by it, but before he can ask, Dumbledore acknowledges that it is a rather unpleasant sight, and says a similar line, "The tale is thrilling, if I do say so myself, but now's not the time to tell it." He then extends his left arm and instructs Harry to take it, which Harry is already to the left-hand side of Dumbledore and he obliges. The hand, curse and appearance aside, does not give Dumbledore any pain in the film.
 * In the book, Harry asks why they went to Budleigh Babberton, and Dumbledore tells him that they are short on staff so they want to convince Slughorn to return. In the film, Harry does not ask, and when asked if he was curious as to why they went there, Harry says that after all the years at Hogwarts, he no longer bothers to question what they do anymore. Dumbledore does not tell him anything about Slughorn or them being short on staff, only telling him to draw his wand, and they proceed to enter the house.
 * Safety measures issued by the Ministry and about the Inferi were not discussed throughout the entire film.
 * In the book, the flaw in Horace Slughorn's plan to hide himself was that he forgot to cast the Dark Mark. In the film, the flaw is the blood on the ceiling, which Dumbledore identified as Dragon blood.
 * In the book Horace Slughorn was said to have a big silver moustache like a walrus and was supposed to be quite large, both are changed for the film. In the film, he does not have a moustache, and is only slightly chubby. Additionally, Slughorn is portrayed as a soft-spoken, senile man in the film.
 * In the book, Slughorn and Dumbledore stand back-to-back, waving their wands to restore the house. In the film, only Dumbledore restores the house, sending everything back together with a single wave of his wand.
 * In the book, Slughorn tells Dumbledore that he took a long time in the bathroom, and asks if it were from an upset stomach. Dumbledore answers that he was reading the Muggle magazines, and admits he loves knitting patterns. Slughorn does not say anything in regards to this matter in the film. Also in the film, Dumbledore returns with the magazine and asks if he could have it, admitting he loves knitting patterns just as in the book.
 * In the book, after the house is restored, Dumbledore, Harry and Slughorn have a drink and talk, before Dumbledore asks to use the bathroom. In the film, Dumbledore goes to use the bathroom right after the house is restored. When Dumbledore returns, he and Harry promptly leave, stating that he knows a lost cause when he sees one, just as in the book.
 * Slughorn tells Dumbledore that the Muggles who own the house are on holiday in the Canary Islands in both the book and film, however, in the book, he says this after the house is restored. In the film, he says this before the house is restored, to which Dumbledore suggests putting the house back in order for its Muggle owners. He then begins to restore the house.
 * In the book, Dumbledore and Harry apparate to the tool shed near the Burrow. Before leaving him, Dumbledore informs Harry that he will be giving him private lessons and tells him to confide the truth about the prophecy to Ron and Hermione as well as to keep his invisibility cloak with him at all times and Dumbledore's praising Harry for the way he has handled his godfather's untimely death. Harry is not told any of this in the film, and after apparating, he finds himself standing on the swamp alone outside the Burrow.

5. An Excess of Phlegm

 * After explaining Slughorn's position, in the film, Dumbledore admits that he fears he might have stolen a wondrous evening from Harry, referring to the cafe waitress, who was not in the book. Harry dismisses this, saying that he will simply return the next day and make up an excuse. Dumbledore tells Harry that he will not be returning to his home that night, his owl and trunk having already been moved. Dumbledore then proceeds to send Harry to the Burrow.
 * In the book, Harry arrives at the Burrow around 1:00 a.m., after Ron and Hermione have gone to bed, and they don't see him until the next morning. In the film, it is unclear exactly when he arrives there (although obviously before so late). While it is dark when Harry arrives, Ron, Hermione, and Ginny are all still awake and go to welcome Harry when he enters the Burrow.
 * In the book Molly Weasley and Tonks see Harry first, meeting him at the door as Dumbledore leaves him in their care. In the film, Tonks is not at the Burrow and instead Ginny finds Harry's owl Hedwig and trunk have suddenly appeared in the house, and asks her mother, Ron, and Hermione if they have seen him. When Harry enters, Ginny ecstatically embraces him, implying that they already have an interest in one another, before Hermione, Ron, and Molly come to meet him, and he is seen hugging each of them as well. Ginny and Harry do not show an interest in each other until later in the book.
 * In the book, Molly appears to have known Harry was coming since Dumbledore said he was, but in the film, since Harry arrived alone, Molly asked why Harry didn't let them know he was coming with Harry answering that he didn't know and that Dumbledore sent him to which Molly replies "Oh, that man. But then, what would we do without him".
 * There is no mention of Arthur Weasley's promotion.
 * In the book, Harry was having onion soup with him and Molly talking about Slughorn and Arthur's promotion and later Arthur comes home and greets Harry and has onion soup as well, then he and Harry bid each other good night. In the film, due to Ron and Hermione being awake and Harry arriving much earlier at the Burrow, he is seen with his two best friends in Ron's room talking and Arthur does not appear in the film until later.
 * There are no security measures discussed or implied before entering the Burrow in the film.
 * Discussion of Bill and Fleur's wedding arrangements, Fleur's stay at the Burrow, and even both characters, have been omitted.
 * The relationship between Tonks and Lupin is implied, as they leave the party together and Tonks mentions that "the first night of the full moon cycle is always the worst." She also calls Remus sweetheart but later in the film. In the book, she was presumably discussing her feelings for and worries about Lupin with Mrs Weasley before Harry arrives. Tonks does not appear on this chapter in the film.
 * Harry, Ron, and Hermione sit around a levitated smouldering wad of the Daily Prophet discussing about Dumbledore, which seemed to be ignited by Harry with his wand. This does not happen in the book and could not because Hogwarts students are not allowed to use magic outside of school. Though, as pointed out later in the book, the trace can only identify that magic has been used, so in magical households it is up to the parent to enforce the rule.
 * There is no scene where the Owls bring the examination results; the first reference to Harry's exam results comes when Professor McGonagall informs him (in the Hogwarts corridor) that he may take potions as he had exceeded expectations in this subject.

6. Draco's Detour

 * Diagon Alley is almost completely boarded up and vacated. The only life to be seen comes from Weasleys' Wizard Wheezes Joke Shop. The "U-No-Poo" posters are not mentioned (though the product is shown in the background, and was created as promotional material for the film). However, there is a statuesque, moving sign of one of the Weasley twins' lifting a top hat to reveal a rabbit. The sign is over a story tall.
 * There is no mention of how the Weasleys were able to open the store because of the winning prize of the Triwizard Tournament held two years before.
 * Igor Karkaroff's murder is not mentioned in the film. However there is an image in of a Daily Prophet article talking about Karkaroff's murder.
 * The scene where the trio meets the Malfoys in Madam Malkin's (and promptly fight) is neither shown or mentioned.
 * In the book, the merchandise Ron wants to buy at Weasleys' Wizard Wheezes costs three Galleons, nine Sickles, and a Knut, and when he asks his brothers for a discount, Fred and George knock one knut off the price. In the film, the merchandise costs five galleons, and when Ron asks for a discount, Fred and George double the price, making it ten galleons.
 * The scene where Ginny asks her mother for a Pygmy Puff is omitted. However, she is later seen on the Hogwarts Express with one sitting on her shoulder, which Luna Lovegood admires and remarks that they have been known to sing on Boxing Day.
 * Draco does not sneak off on his own and talk to Mr Borgin about fixing the cabinet, but instead goes with his mother and several Death Eaters. Harry, Ron, and Hermione do not follow him under the cloak and use extendable ears, and Hermione does not try to trick Mr Borgin into telling her what Draco is reserving.
 * Borgin and Burkes appears with a sign without the 's' at the end of Burkes. There is a WANTED poster of Fenrir Greyback in Knockturn Alley. The trio climbs the dilapidated roof of an abandoned building to witness Draco being shown one half of the pair of vanishing cabinets, instead of listening to Malfoy about wanting to fix something, from the beginning they know that the object that Draco wants is the vanishing cabinet, the cursed necklace is not mentioned nor seen. The cabinet is triangular-shaped and monolith in size.
 * There is no mention of fake amulets, etc. being sold.

7. The Slug Club

 * In the film, Harry, Hermione, and Ron are not seen back at the Burrow after spying on Draco. Instead, they are next seen on the train, and it is here that they discuss what Draco may have been doing at Borkin and Burkes in the film.
 * In the book, Harry asks if he could share a compartment with Ginny on the train, but she has to go and see Dean, and Harry shares a compartment with Neville and Luna instead. In the film, he shares his compartment with Hermione and Ron, while Luna is seen in the corridor selling issues of the Quibbler to Ginny and Dean.
 * The Slug Club's first meeting does not take place at Slughorn's compartment in the Hogwarts Express, but at Slughorn's office in Hogwarts.
 * The Slytherin end of the Hogwarts Express is split into two sides, not compartments as had been seen in previous films. It looks like booths with a table in between them. There is no door to close as had been in previous films. The compartments where Harry, Ron, and Hermione sit are similar to what was in previous films, with the sliding doors.
 * Since the Slug Club meets later in the film, Harry goes right to spy on Draco when leaving his compartment.
 * In the book, Harry follows Blaise Zabini into the Slytherin's car, while under his invisibility cloak. In the film, Harry uses Peruvian Instant Darkness Powder, creating a thick, dark cloud of smoke to engulf the coach, while he climbs undetected onto the luggage rack, and remains there under his cloak for the duration of the journey, as he does in the book.
 * Pansy Parkinson sits beside Blaise and across from Draco in the film, rather than beside Draco, stroking his hair. Very little of her as well as her relationship with Draco is seen in the film series as a whole.
 * The Hogwarts Express is shown to have five coaches, instead of the usual four coaches as shown in the previous books.
 * In the book, Draco criticises Professor Slughorn and his Slug Club members while with Pansy and Blaise, then talks to them about how he may not return to school for the next year, saying he has to do other things. As the Slug Club does not occur at this point in the film, Draco simply criticises the school, and the only thing he says that might suggest he will leave the school is that he tells Blaise that he will probably not be seen wasting time in Charms class. Blaise laughs at this, to which Draco says, "We'll see who's laughing in the end..."
 * When the students are shown leaving the train to go to the school, most have not yet changed into their school robes, rather going clad in modern clothing.




 * The scene in which Draco catches Harry spying on him on the train is performed much as it is in the book, though Draco does not tell Harry how he knew Harry was there, just asking if Harry's mother told him it was rude to eavesdrop. When Draco uncovers Harry after sending him to the floor, he steps on Harry's nose in revenge for his father's imprisonment, just like in the book, but does not take care to step on Harry's fingers.

8. Snape Victorious

 * The way Harry is found is different in the film. In the book, Tonks finds Harry, stating that she did not see him leave the train and, knowing Harry has his cloak, decided to double check the train. In the film, it is Luna Lovegood who finds Harry with her Spectrespecs, stating that she can see Wrackspurts all over him.
 * Harry Potter is not met at the gate by Snape. Instead, Professor Flitwick stops Harry and Luna and then casts a non-verbal spell to the gate for defence. Also, Snape does not take Harry to the castle; instead, Harry and Luna walk by themselves, while Snape is seen vouching for Draco to get him past the security measures.
 * Because Nymphadora Tonks was replaced by Luna in saving Harry from the train, the film does not show Tonks' Patronus and also due to the replacement, Luna also fixes Harry's nose with Episkey.
 * When Harry enters the Great Hall, his nose is bleeding, as in the book, but Hermione does not perform the Tergeo spell to heal it. Instead, Ginny lends him a hankerchief to wipe off the blood.
 * Also, in the novel, when Harry enters the Great Hall, he is still wearing his normal clothes because he did not have enough time to change into his robes, but in the film, he is wearing his school robes.
 * When Dumbledore speaks in the Great Hall, Hermione asks about his injured hand, and many others start to whisper upon seeing it. Dumbledore dismisses it, saying it's nothing to worry about, and covers it with his sleeve. Hermione does not say anything about it in the film, and aside from Harry, the injured hand goes pretty much unnoticed.
 * Hagrid is present in the Great Hall, instead of being in the forest with Grawp.
 * Dumbledore's speech in the book explicitly states that Lord Voldemort is once again at large, and advises everyone to be careful and report any suspicious acts. In the film, however, he is more subtle, explaining that there was once a boy who attended the school, appearing to be a student like any other. The name Voldemort is not spoken, instead Dumbledore says this boy was named Tom Riddle, but is currently known around the world by another name. He goes on to state that, while at any moment there are dark forces attempting to enter the castle, "... in the end, their greatest weapon is you..."
 * Harry does not appear to be furious about Snape's appointment as Defence Against the Dark Arts teacher, nor are any D.A.D.A. classes shown throughout the film. It should be noted that, in the Order book, Harry partly blamed Snape for Sirius's death, causing Harry to hate Snape even more. However, in the film, Harry did not blame Snape, as the latter didn't have much contact with Sirius as he does in the book.

9. The Half-Blood Prince

 * Discussion about choosing subjects and questioning of Prof. McGonagall were also not included in the film. Simply Professor McGonagall is seen in the corridor giving class schedules to students and then chastising Harry and Ron for laughing at the newer students. She then instructs Harry to take Potions lesson and to bring Ron with him.
 * In the film, when Harry and Ron entered the Potions class, they are both late, but Slughorn does not seem to have started the lessons yet. The two informed Prof. Slughorn that they do not have the required book, so Slughorn instructs them to get a book from the cabinet inside the room. When they see that there is only one new book left, they both grab for the new version of the book, titled Advanced Potion-Making. Ron successfully got the new book while Harry is left with the older copy, formerly property of the Half-Blood Prince. In the book both Ron and Harry get an old copy (both handed by Slughorn), with Ron's even having what he described as looking like a vomit stain.
 * In the book, Harry, Ron, and Hermione are the only Gryffindor students to take Slughorn's N.E.W.T. Potions class. In the film, many other students are present in Slughorn's class as well, including Dean Thomas, Seamus Finnigan, Neville Longbottom, Padma Patil, Lavender Brown, Romilda Vane, and Katie Bell, despite Romilda and Katie not even being in the same year as Harry and the others. In the film, Crabbe and Goyle are in the class as well, despite the book specifically stating that they were not. Pansy Parkinson also appears, although in the novel there was one unspecified Slytherin student in the class with Draco Malfoy, Blaise Zabini, and Theodore Nott.
 * In the book, the Felix Felicis is gold. In the film, it is clear.
 * In the book, Professor Slughorn says that one bottle of Felix Felicis lasts for twelve hours, and that the one who takes it will be lucky at every endeavour from dusk to dawn. In the film, he says that the one who takes it will succeed at every endeavour until its effects wear off, with no mention made of exactly how long it lasts.

10. The House of Gaunt

 * The Gaunt scene is cut. Yates stated, "In the books, the memories were a very big part of JK Rowling's story. We've actually pared them down in our story, and she was very supportive of that decision. They're such an enjoyable part of reading the Half-Blood Prince. But we've kind of distilled them down to two or three memories to try to keep everything more in the moment. Flashbacks in films are tricky things; they tend to hold up the momentum of the story you're telling."The creators felt it more important to concentrate on Riddle as a young boy.
 * The film only shows the memory in which Dumbledore goes to pick up Voldemort at the orphanage and the memory in which Voldemort asks Slughorn about the Horcruxes, which is shown twice, as in the book.
 * The injury on Dumbledore's hand, though present, is not emphasised as much as it is in the book. Harry never asks about it, and the only further mention about it is when Dumbledore raises the injured hand as he mentions that the ring is difficult to destroy, suggesting it injured him during his attempts to destroy it. The injury would not be further explained until the final film.
 * Dumbledore only refers to Merope Gaunt as "Voldemort's mother" when Harry asked about the ring. He tells Harry that the ring belonged to Voldemort's mother, when in the book it was retrieved in the hands of his uncle Morfin, and is actually an heirloom from the Peverell family.
 * The Resurrection Stone mounted on the ring is cracked down the middle, right through the symbol of the Deathly Hallows. However, in the film, the stone remains intact, but seems to have been purified, and is seen as clear rather than coloured.

11. Hermione's Helping Hand

 * During the Gryffindor Quidditch tryouts, instead of having each position try out separately (like in the book), Harry has all the positions play together, making it like an actual match without a Seeker.
 * Hermione does use the Confundus Charm against Cormac McLaggen, however the spell is whispered into her hand in order to hide the incantation. Also, the incantation she uses is not the correct one. It is revealed in that the proper incantation is "Confundo". In the film, Hermione says "Confundus."
 * In the book, Harry, Hermione, and Ron had seen very little of Hagrid for some time. He had not been attending meals, and was not seen around the school very much, and whenever they did see Hagrid, he would fail to acknowledge them. Finally, the three visit Hagrid at his hut, and notice he has a barrel of foot-long maggots, which he tells them is food for Aragog. Hagrid goes on to tell Harry, Hermione, and Ron that Aragog got sick over the summer and was not getting any better, and Hagrid fears Aragog may be dying. In the film, Hagrid is only seen in the background, if at all, between taking Katie to the castle and Aragog's funeral, and no mention of Aragog, his health or otherwise, is made prior to his death.

12. Silver and Opals

 * The scene where Harry, Hermione, and Ron meet Slughorn is moved from Honeydukes to the Three Broomsticks Inn. During the scene Slughorn mistakenly calls Ron "Wallenby". This is presumably a reference to Harry Potter and the Goblet of Fire where Mr Crouch repeatedly calls Percy "Weatherby". In the book, Slughorn would mistakenly call Ron "Ralph."
 * In the film, Ginny, Dean and Malfoy are seen in the "Three Broomsticks", but in the book, Ginny and Dean are in Madam Puddifoot's Tea Shop during this time, and Draco was serving detention with Professor McGonagall for having not completed his Transfiguration homework for the second time in a row.
 * In the book, when Slughorn finds Harry in Honeydukes, he tells Harry that he had missed the third supper party that Slughorn held (as Harry always held Quidditch practise whenever they were held) and invites him to another. In the film, this particular supper party is apparently the first (and possibly the only) one to be held during the term. In the book, Harry says he has to meet Dumbledore and thus is unable to attend, but in the film, he gladly accepts the invitation. Slughorn also invites Hermione to the supper party, whereas she had been attending the previous parties in the book. In the film, Ron asks Harry what he was "playing at" with Slughorn, and Harry says that Dumbledore wanted him to get to know Slughorn better.
 * In the film, Hermione appears to act tipsy after the three leave the Three Broomsticks, possibly from drinking excessive amounts of butter-beer, though she sobers up immediately upon discovering Katie Bell.
 * Katie Bell is cursed by the necklace as in the book, and she is lifted into the air and silently screams with her head tilted back in a very frightening manner. As in the book, Hagrid comes and takes her to the castle, however Hagrid's role on the whole is very diminished.
 * Harry doesn’t meet Tonks and Mundungus Fletcher at Hogsmeade.
 * In the book, Leanne is crying when she tells McGonagall about what happened, but in the film she is calm.
 * In the film, Snape is called over to examine the necklace, and upon examining it, concludes that Katie is lucky to be alive. When Harry is asked what evidence he has that Draco cursed Katie, in the book, he tells McGonagall about how he, Hermione, and Ron followed Draco to Borkin and Burkes. In the film, he says he "just knows...", and Snape chastises him for being so confident about his accusation.

13. The Secret Riddle

 * In the film, the memory of the Wool's Orphanage doesn’t include talks of Tom Riddle hurting kids at the cave, of which only a crude picture is shown taped up on Riddle's bedroom wall. However, there is a deleted scene where Dumbledore tells Harry about Tom doing so when they are at the cave's entrance later in the film.
 * Mrs Cole taking Dumbledore into her room to talk about Tom Riddle is omitted. But the former and latter are seen walking up the stairs and on Tom's floor where she tells Dumbledore that in all the years Tom was in the orphanage he never once had a family visitor and that there had been nasty incidents with the other children.
 * In the novel, Mrs Cole mispronounces Dumbledore's name by first calling him Dumberton by mistake. But when she tries to correct herself, she mispronounces his name again by calling him Dunderbore. In the film, Mrs Cole is able to pronounce Dumbledore's name correctly without making any mistakes as we hear her calling him 'Mr Dumbledore'. This is most likely because the film deleted the drinks she had with Dumbledore while talking about Riddle in her room before introducing Dumbledore to the boy.
 * Tom doesn't ask whether his father was a wizard and doesn't mention his thinking that his mother must have been a Muggle since she didn't survive.
 * In the novel, Dumbledore pours the memory into the Pensieve and accompanies Harry into the memories. In the film, Dumbledore gives Harry the memory to pour, and Harry enters them alone, with Dumbledore standing back and observing.

14. Felix Felicis

 * In the film, at breakfast before the first Quidditch match, Luna Lovegood, not Hermione, notices Harry faking to slip Felix Felicis into Ron's drink.
 * The weather on the day of the first Quidditch match is snowing and stormy in the film, whereas in the book it is clear, a circumstance which Ron attributes to the Felix Felicis he thinks he drank.
 * Zacharias Smith does a commentary during the Quidditch match in the book, while there is no commentary during it in the film.
 * Only a part of the match is shown. Ron saves several goals, then Ginny scores a goal. Ron saves one more goal and the crowd starts chanting for him. Directly afterwards, the scene changes to a party in the common room, and it is implied that Gryffindor won. Harry is not seen catching the Snitch and end the game (in fact, Harry is only seen once during the match, and it is very brief. He is far away, hovering next to Ron when the Gryffindors start their offensive play).
 * Neither Harper nor Malfoy are seen playing on Slytherin's team in the film, though since only part of the match was shown, they could have simply been off camera.
 * The scene in which Ron and Ginny have a fight is omitted. It is never said that Hermione had possibly kissed Krum, so Ron never gets angry with her. Thus, Ron could not have been dating Lavender to get revenge. Instead, he might have actually had interest in her, though it turned to annoyance.

15. The Unbreakable Vow

 * The discussion between Harry and Hermione inside the Hogwarts Library is included. Romilda Vane was introduced but she does not speak. Madam Pince is not present in the film.
 * In the book, Harry invites Luna to Slughorn's party as friends. In the film, he makes the same offer to Hermione, who likes the idea but has already arranged to go with McLaggen (in order to annoy Ron). Harry says he'll find another date and the scene cuts to him meeting Luna.
 * Professor Trelawney is not present, Eldred Worple, Sanguini and other guests were not introduced by Prof. Slughorn but Filch's interruption holding Draco and telling everyone he is gatecrashing is included.
 * There is much less conversation between Draco and Snape. Snape only mentions to Draco that he has made an Unbreakable Vow, then Draco emphasised that he doesn't need protection. Harry eavesdrops on the conversation, like in the book, but rather than using his Invisibility Cloak, he just hides around a corner.

16. A Very Frosty Christmas



 * There has been an additional scene in the film which has no book equivalent. The Burrow is attacked by Death Eaters during the Christmas holidays. Bellatrix Lestrange and Fenrir Greyback are the only Death Eaters shown. Greyback flies and lands in a ball of flame and casts a ring of fire around the Burrow (possibly Fiendfyre, as the flames are quite large and take the form of a serpent). Lestrange lands in black smoke and taunts Harry, chanting "I killed Sirius Black! I killed Sirius Black!" Harry takes off after her in rage. Ginny takes off after him, trying to stop him. Lupin, Tonks, and Arthur Weasley follow them into the grassy marsh. While the five are lost in the field, looking for the Death Eaters, the Death Eaters take off and set the Burrow aflame, burning it presumably to the ground, before leaving. There is no further mention in the film of how the home is restored or what happened to it afterwards. The Burrow was supposed to be protected against the Death Eaters, and they simply set fire to it with no effort. By the time Harry returns to it in the film adaptation, the Burrow had already been rebuilt.


 * The discussion of Remus and Harry about Snape's character is shorter. Remus Lupin does not reveal to Harry that Snape helped him while he taught at Hogwarts as D.A.D.A. professor by brewing him a Wolfsbane Potion every month.
 * The film omits the details that Fenrir Greyback is a werewolf, and also the part of Lupin mentioning that Greyback was the one who turned him into a werewolf.
 * No reason is shown for Tonks's lack of colour in her hair (it is brown, not pink). The book explains that it was because she was in love with Lupin and worried for his safety amidst the werewolves and also anxious because he could not communicate with her.
 * In the film, the part where Percy Weasley arrives at the Burrow on Christmas Day with the new Minister for Magic Rufus Scrimgeour is omitted, including the part where Scrimgeour attempts to persuade Harry to help the Ministry to tell to the Wizarding world that the Ministry's doing a wonderful job.
 * In the film, the necklace is a gold heart with an arrow through it, rather than the words "My Sweetheart". Ron does not receive it from Lavender for Christmas, rather, she is seen giving him it once they are back at school and Ron agrees to wear it, much to Hermione's disgust.
 * The part where the characters are listening to the music of Celestina Warbeck is omitted.
 * The Christmas season shown in the film is a big contradiction on what the Chapter's title is. There are no signs of snow outside the Burrow and Ginny's nightdress seems unfit for a frosty season.
 * Also included in the Christmas celebrations at the Burrow are several scenes of suggested romance between Harry and Ginny. In the book, Ginny did not show clear signs of affection toward Harry until after they started going out.
 * It is implied that Tonks and Remus are already going out, as she seems to know Remus's transformation habits and calls him, "sweetheart". The Burrow sequence is their only appearance in the film; the only aspect of Tonks' personality changes from the book in evidence is that she appears to be more subdued than her previous appearance.

17. A Sluggish Memory

 * The memory of the Gaunt House, Merope with the locket, Voldemort going to kill the Riddles and stealing the ring, the memory of Voldemort working at Borgin and Burkes and wanting the cup and locket, and the one when Voldemort returns to the school to ask to teach have all been omitted. Only the memory of the orphanage and of Voldemort asking about Horcruxes were kept.
 * There's no mention of Tom killing the Riddle family.
 * Slughorn's false memory does not show cloudiness; instead, when Riddle asks about Horcruxes his voice becomes muted and Slughorn rebukes him angrily. Also, significantly, the word "Horcrux" is heard, but very silently.

18. Birthday Surprises

 * There are no Apparition lessons or examination taught by Wilkie Twycross.
 * In the book, Ron and Lavender break up due to Lavender seeing Ron and Hermione coming down from the boys' dormitory (not seeing Harry due to him hiding under his invisibility cloak) and assumes they were together.
 * When Ron eats the chocolates, which had the love potion and was intended for Harry, becoming lovestruck, and ultimately falls prey to Slughorn's poisoned meade, was changed. In the book, this was all on his birthday, and Slughorn, Harry, and Ron toast to Ron's birthday, wishing him to have many more memorable birthdays. In the film, the events happened on Valentine's day, and the toast was "To life!"
 * When Ron is brought to Slughorn's office, Slughorn mistakenly refers to him as "Wemby" in the film. In the book, Slughorn calls him "Ralph". Also in the book, Slughorn later tells Harry that he has had every bottle tested by a house elf since Ron's incident, mistakenly referring to Ron as "Rupert," likely a reference to the actor who plays Ron in the film series, Rupert Grint. There is no mention of any precautionary measures taken by Slughorn in the film.
 * During the scene where Ron is in Slughorn's office, Ron accidentally mistakes Slughorn for Romilda and hugs him. In the book, Ron is aware of who Slughorn is and is trying to shove him away to get to Romilda in the doorway.

19. Elf Tails

 * The Quidditch scene and Luna's Quidditch commentary from this chapter have been cut.
 * The film doesn't show Harry being admitted to the hospital wing, due to the absence of the Quidditch match and McLaggen having knocked him off his broom with the Bludger.
 * No appearance nor mention of Dobby working in the Kitchen at the Castle, nor of Dobby and Kreacher tracking Draco for Harry.
 * In the film, Ron mutters Hermione's name while unconscious at the hospital wing with Harry, Hermione, Lavender, Ginny, Dumbledore, McGonagall, Pomfrey, Slughorn, and Snape present, and Lavender runs off in tears. This is how Ron and Lavender break up in the film and is the first time Lavender's name is mentioned in full.
 * The visiting of Hagrid, Fred, George, Arthur & Molly Weasley for Ron while in the Hospital wing were not shown in the film. The praising for Harry using a bezoar as an antidote to the poison is not mentioned by Fred but instead by Prof. Dumbledore.
 * When Hagrid is visiting Ron, he tells Harry about an argument between Snape and Dumbledore that he had overheard. Hagrid is not seen visiting in the film, and the argument occurs later.

20. Lord Voldemort's Request

 * The memory showing Hepzibah Smith and House-elf Hokey were not shown nor mentioned in the movie, and Voldemort applying for the D.A.D.A position is also omitted. Dumbledore also does not scold Harry for his inability to obtain the unaltered memory from Slughorn.
 * Prof. Dumbledore didn't mention to Harry that this position is possibly cursed by Voldemort because he refused Voldemort's request, in that no one can retain the position for more than one year. In the film's original script, it is suggested by Ron earlier at the opening feast (counterpart of the chapter "Snape Victorious"), stating "That job's jinxed. No ones lasted more than a year." and "Personally, I'm going to keep my fingers crossed for another death." But it is never explained who has jinxed the job, why, or, for that matter, if the job was actually jinxed at all.

21. The Unknowable Room

 * The scene where Harry notices Malfoy disappearing from the Marauder's Map when he enters the Room of Requirement is omitted from the film, but it is featured as a deleted scene on the DVD releases.
 * There is no mention of Crabbe and Goyle using Polyjuice Potion and standing guard for Malfoy outside of the Room of Requirement.
 * Draco is seen testing an apple on the vanishing cabinet. It comes back with a bite taken out. He then tests a white songbird in the cabinet, and it comes back dead. Draco's desperation and fear in this scene are palpable. It is likely that he was repeatedly testing to see if it would work correctly, and became more frightened the more the tests failed, as everything he sent through except for the black songbird came back damaged in some way. It is also possible that the white and black songbirds and their respective failure and success may be an act of symbolism or foreshadowing, as well as demonstrating the cabinets' tempermental nature.
 * Tonks doesn't appear inside Hogwarts looking for Prof. Dumbledore.

22. After the Burial

 * The trio didn't receive a letter from Hagrid informing them that Aragog was dead. Instead, Harry simply mentioned that he wants to go to Hagrid's place after drinking the Felix Felicis.
 * Instead of taking a few drops of the Felix Felicis, Harry drains the entire bottle.
 * Slughorn is seen stealing tentacula leaves, rather than working WITH Professor Sprout to obtain potions ingredients.
 * Aragog's size appears smaller than described and shown in both the books and the second film adaptation.
 * Slughorn also asks Hagrid for the venom directly rather than sneaking a couple bottles as he does in the book.
 * Harry doesn't talk about Lily and James death to Slughorn to the extent that he does in the book.
 * In the film, Slughorn talks about a present that Harry's mother, Lily Evans once gave him. The present was a bowl with a few inches of clear water.Mourning_of_Aragog.png There was a petal, floating on the surface, which gradually sank and turned into a fish just as it reached the bottom. The fish was named Francis. Slughorn discovered that the fish disappeared the day Lily Evans died. In the book, however, there is no mention of the present; Harry brings up the topic of his parents' death after Hagrid mentions them just before falling asleep.
 * Harry, Slughorn, and Hagrid sing a song while drinking after mourning Aragog. In the film, this scene is shortened, and only the final verse is heard.

23. Horcruxes

 * Only the ring and diary are mentioned to be horcruxes. The ring, which is supposed to be set with a plain round stone bearing a crude carving of the Deathly Hallows, is instead set with a fluorite-cut, honey-brown gemstone.
 * Dumbledore does not actually have possession of Tom Riddle's Diary as it is shown in the film; Harry gave it back to Lucius at the end of Chamber of Secrets. (However, Lucius gave the diary to Dobby, and Dobby may have given the diary back to Harry or Dumbledore). One thing that people may have noticed is that in the Harry Potter and the Chamber of Secrets movie, Tom Riddle's diary (after it is destroyed) shows only a small hole in the middle, but in this film, it looks as though a small bomb exploded in it.


 * As noted, the cup and locket story is left out, and something of Gryffindor or Ravenclaw and Nagini are not debated to be horcruxes. However, cases of swords are seen to be mounted to the balcony wall in Dumbledore's study.
 * Dumbledore only mentions that the horcruxes could be anything, thus it implies that they don't know what they could be, Dumbledore never mentions that Voldemort searched for treasures and that it might be possible that his horcruxes were Valuable treasures of Hogwarts founders. Harry never gets to know how Dumbledore found out about the cave.


 * Dumbledore and Harry do not have many talks about Voldemort like they did in the book. Voldemort is not explained as someone who likes to control people, who is very charming with all the teachers, who places great meaning on places where he has tortured others, and who feels a deep connection to Hogwarts because it is proof he is special and is a wizard and because it feels like his home. However, these details were focused on in the Chamber of Secrets film.

24. Sectumsempra
"I know what you did, Malfoy. You hexed her, didn't you?"
 * The duel between Harry and Draco at the bathroom took place just after Harry questioning Katie Bell in the Great Hall regarding the cursed opal necklace. Katie looks at Draco then suddenly Harry chases him. In the book, the questioning of Harry on Katie Bell and Harry's duel with Draco took place between a couple of days and did not happen in the same day. In the book, Harry was tailing Draco using the Marauder's Map until he saw Draco inside the Boy's bathroom on the sixth floor. He overheard Draco crying and saw that he was accompanied by Moaning Myrtle, who is absent from the film.
 * In the film, Malfoy is running away from Harry and goes into a bathroom on the seventh floor, near the Room of Requirement. In the book, the bathroom that the duel takes place in is not on the seventh floor.
 * Harry and Draco briefly duel before Harry uses the Sectumsempra spell and Snape's counter-curse Vulnera Sanentur is an incantation rather than a song.
 * The duel is longer and more intense in the film. In the book, Malfoy turns around and attacks, and Harry almost immediately uses sectumsempra after the two of them cast about two spells each at each other. In the film, Harry and Malfoy shoot several spells at each other, hide behind stalls and shoot spells at each other underneath the stalls, run around the stalls while shooting spells at each other and finally Harry uses Sectumsempra on Draco when he sees him standing on the other side of the bathroom, directly after coming out from under cover.
 * In addition, the duel is composed of simple non-verbal duelling spells. Draco is not heard trying to use the Cruciatus Curse.
 * Directly before Malfoy attacks Harry, Harry talks to him, saying
 * The scene where Severus Snape gives Harry detention for the Sectumsempra spell/ownership of his textbook is cut and apparently never took place. This creates a plot hole in the film as Harry apparently gets away with using a potentially deadly spell against a classmate with no apparent punishment (this could also be seen as telegraphing the revelation that Snape is the Half-Blood Prince). Even more so since Malfoy was not trying to use Crucio as he was in the book. It is, however, possible that Harry did get punished, but it happened off-screen, with the film chosing to highlight Harry's remorse instead.
 * Ginny, not Harry, hides the textbook in the Room of Requirement. In the final book, Harry knows where to find the diadem horcrux based on where he hid the book. In the final film, Harry knowing the diadem and Half-Blood Prince's books' locations are unrelated to each other.
 * In the same scene, Ginny kisses Harry and they both keep it secret. In the book, however, they kiss in full public view after the Quidditch match between Gryffindor and Ravenclaw (during which, Harry was in Snape's detention); in the film, a scene with Ron and Lavender kissing under identical circumstances appears instead. Also, they find a second songbird Draco tested on the cabinet, a black one, alive and singing, but they do not know its significance. The cabinet is covered by a tapestry and they do not see what it is.
 * Also, when Ginny kissed Harry, it was never revealed how or when she had broken up with Dean Thomas. Indeed, very little of her relationship with Dean is depicted in the film compared to the book. In the film, they are only seen together in the Three Broomsticks when they were snogging. After that, the only further mention of their relationship was when Hermione noticed Ginny's eyes at Slughorn's dinner party, and she tells Harry that they have been fighting. They were apparently still together, as Harry was not able to ask her to Slughorn's Christmas party, but they apparently ether have broken up or were on the verge of a breakup closer to Christmas, as evidenced by her time with Harry while at the Burrow for the holiday.

25. The Seer Overheard

 * Emma Thompson does not return as Professor Trelawney and the scene where Snape's role as double-agent is not shown or mentioned.


 * The film doesn't show Harry questioning Dumbledore as to why he trusted Snape.
 * The scene where Harry gives the rest of the Felix Felicis to Hermione and Ron before meeting Dumbledore is omitted, as Harry had finished the bottle.
 * Snape's argument with Dumbledore, which took place at the Forbidden Forest at night and is overheard by Hagrid, who disclosed to Harry in the book, is changed to taking taking place at the Astronomy Tower during the day, shortly before Harry arrives to meet up with Dumbledore. Snape argues that Dumbledore takes too much for granted and that he does not want to do what was asked of him, which is the same argument that Hagrid hears in the book. Snape starts to leave after Dumbledore dismissed him, pauses for a moment upon seeing Harry, then leaves the tower.
 * In the book, Dumbledore and Harry (who was under the invisibility cloak) walk till the Hog's Head in the village of Hogsmeade, from where they Disapparate to the cave. In the film, they Disapparate from the Astronomy Tower in Hogwarts. Although often cited as a continuity break with the other films and the novels (which establish that one cannot apparate from within Hogwarts' grounds), in fact the Half-Blood Prince novel establishes that Dumbledore is able to remove the enchantment preventing this from certain locations, specifically (in the book) the room where apparating lessons are held; this is also supported by Dumbledore's comment in the film about having certain privileges as headmaster.

26. The Cave

 * In the book, Harry and Dumbledore have to swim from the rock they arrive on to the cave entrance. In the film, they are briefly shown standing on the rock, with waves crashing around it, the sea seemingly too rough to swim across.  The scene cuts to the two at the cave entrance, not showing how they got across.
 * The scene in which Dumbledore gives Harry the back-story involving a young Tom Riddle bringing Amy Benson and Dennis Bishop from Wool's Orphanage to the Crystal Cave was filmed, but cut from the final production and is featured as a deleted scene on the DVD releases.
 * Once in the cave, Dumbledore does not ponder about how to access the hideout as in the book, rather, he appears to have already known how, as he promptly cuts himself and tells Harry that payment must be made to enter.
 * The boat used by Prof. Dumbledore and Harry to go to the island in the lake is not as small as described in the book.
 * In the book, Dumbledore attempts to reach into the potion to grab the horcrux, but an invisible barrier prevents him from penetrating the potion and he realises that the potion cannot be penetrated by conventional means and begins pondering about how to reach the horcrux. In the film, Dumbledore similarly attempts to penetrate it, but is only able to touch the surface, then he immediately concludes the potion must be drunk.
 * The potion in the basin was black rather than glowing green in the film, and the goblet used to drink the potion was replaced by a shell, which was placed beside the basin rather than summoned by Dumbledore using a non-verbal spell.
 * In the book, Dumbledore drinks about three cups of the potion before falling prey to its effects. In the film, he starts reacting after his first drink. In the book, the potion eventually causes him to faint, but in the film, while suffering badly from the potion, he manages to remain concious the entire time.
 * When Harry tries to get Dumbledore water from the basin, he fills the cup, but the cup is empty by the time he gets it to Dumbledore. In the film, when Harry attempts to scoop out water with the shell, the water seems to go right through the shell as though it were a ghost.
 * In the film, the spell Lumos Maxima is shown again, this time as a glowing ball of light that could be thrown rather than a more powerful version of Lumos.
 * Though the Inferi in the book climb out of the lake and attempt to drag Harry back in with them, they actually pull him underwater in the film.
 * Rather than trap them on the island with a lasso of fire as he does in the book, Dumbledore attacks the Inferi by conjuring a massive wave of fire (which could be a controlled version of Fiendfyre ), then parts the flames using a spell that was not mentioned in the book.
 * In the book, Dumbledore is left in a considerably weakened state after drinking the potion, which continues up to his death. This is less evident in the film.

27. The Lightning Struck Tower

 * When returning from the cave, Harry and Dumbledore appear on High Street in Hogsmeade, where they encounter Madam Rosmerta(absent from the film), who warns them that the Dark Mark has appeared over the Astronomy Tower. Harry and Dumbledore borrow her broomsticks and head up there. In the film, Harry and Dumbledore Apparate there directly. There is a dark, uneasily tranquil feeling conveyed as views of various parts of the school are shown, as though something bad would happen at any moment. However, the Dark Mark is not cast over the school until after Dumbledore's death.
 * Harry is not frozen by Dumbledore as in the book, rather, Dumbledore instructs Harry to go and hide below, and not to speak or be seen by anyone. Harry hesitantly oblidges and goes down to the floor below the top of the astronomy tower looking up through floorboards at the events. In the book, he remains unnoticed the whole time, while in the film, Snape catches Harry in the tower, and persuades him to stay silent, before going upstairs to kill Dumbledore.
 * In the book, Amycus Carrow finds Draco with Dumbledore, and he pressures Draco to kill Dumbledore. In the film, while Amycus is still present, it is Bellatrix Lestrange, who is not among the Death Eaters present in the book, encountering Draco and pressuring him to kill Dumbledore.
 * The scenes in which the moniker "Half-Blood Prince" are explained in detail are whittled down to a single line in which Snape states "I am the Half-Blood Prince," and walks off into the night. The meaning behind the title of the book and film is cut. It isn't found out why Snape was the Half-Blood Prince (He is half-blood and his mother's maiden name was Prince)
 * In the film, Draco shows Dumbledore that he has been branded with the Dark Mark, whereas in the book this is only an assumption by Harry, with no solid proof.
 * In the novel, it is said that Dumbledore appeared frozen in the sky (although this was in Harry's perspective, for the sake of drama). In the film Dumbledore immediately falls over the railing and down towards the ground.
 * In the novel, it says that a bright green light hit Dumbledore (Avada Kedavra), while in the film, its more of a cyan colour.

28. Flight of the Prince

 * The ensuing battle between Hogwarts staff and students against Death Eaters has been significantly reduced to a rampage through Hogwarts; with Bellatrix Lestrange shattering the windows and other glass objects in the Great Hall. The castle appears to be deserted except for one Auror on duty, who Snape jinxes out of the way. The battle was so reduced because the film's producer felt it was too similar to the battle that would occur in the final film.
 * Bill Weasley does not appear in the film, much less get bitten by Fenrir Greyback as he does in the book. However, in the next film, he is shown bearing scars from being attacked by Greyback. This creates a plot hole in the next film since it is unknown where, how and when the scarring happened.
 * Furthermore, the role of Bellatrix Lestrange has been greatly expanded in the film. In the book, she does not fight in the Battle of the Astronomy Tower or witness Dumbledore's Death. Upon witnessing it in the film, she reacts by destroying everything with sadistic glee and delight.
 * In the film, Draco's reluctance to go with the Death Eaters is much more obvious.
 * In the book, Snape reacts with livid emotion when Harry calls him a coward. However in the film, although Harry hurls this same insult at Snape, he does not react.

29. The Phoenix Lament

 * Rubeus Hagrid's cabin is set on fire by Bellatrix Lestrange intentionally instead by Thorfinn Rowle due to the wand battle. The film doesn't show if Fang was trapped inside the hut and also Hagrid is not present in this scene. Harry and Hagrid didn't put out the fire using the Aguamenti Charm.
 * Professor McGonagall joins the crowd who discovered Albus Dumbledore's body in the foot of the Astronomy Tower. She leads the Hogwarts students and staff in raising their wands to be rid of the Dark Mark and in respect for the now-deceased Headmaster.
 * In the book, Harry opens the false locket when he was sitting by the deceased Dumbledore, noticing it is smaller than the one seen in the memory (omitted from the film), and lacks the distinct Slytherin "S" symbol. He then opens it, and holds the note to the light made by the school staff and students, and reads it. In the film, he just clutches the locket in this scene. Later, when he, Hermione, and Ron were in the Astronomy Tower, Harry hands Hermione the locket, and tells her that it was a fake. She then proceeds to open it and read the note.
 * In the book, Dumbledore appears to be bleeding from his mouth after being killed, and Harry wipes off the blood with his (Harry's) own sleeve as he kneels by the headmaster's body. In the film, Dumbledore is not bleeding, and Harry just strokes Dumbledore's hair and puts his hand to Dumbledore's dormant heart. Also in the film, Ginny is seen going over to sit beside Harry and he leans on her shoulder sobbing.
 * Ginny comforts Harry, but she does not escort him to the hospital wing. This also omits the scarring of Bill Weasley and Fleur Delacour still wishing to marry him.
 * Also, since the visit to the hospital wing is omitted, Ron, Hermione, Neville, Luna, Ginny, Professor McGonagall and Madam Pomfrey are already standing in the courtyard with everybody else and staring down at Dumbledore's dead body, while Lupin, Tonks, Arthur and Molly are not present and Bill and Fleur are omitted from the film.
 * Since the memory featuring the locket is not in the film, Harry wasn't able to compare it to the one in the cave, so he may have discovered it was fake when he opened it.
 * There was also no debate or meeting at Headmaster's office between professors to discuss whether or not Dumbledore would be buried on Hogwarts grounds.

30. The White Tomb

 * The entire funeral scene is cut, and the last scene is the trio watching Fawkes flying away through the blue sky. In this scene Hermione mentions to Harry that Ron does not mind him being with Ginny, but they should still keep their snogging minimal whenever Ron is around.
 * It is inferred that Ginny and Harry's relationship is still going strong, although in the book they split up on Harry's insistence that it's not safe for her to be close to him.
 * In the film, Harry finds Dumbledore's wand in his office after the Headmaster's death. This may be a significant aberration from the book where the wand is entombed with Dumbledore's body, though this scene obviously takes place before the burial because the Elder Wand is seen in Dumbledore's tomb at the end of the first part of the film adaptation of .

1. The Dark Lord Ascending

 * In the film, Severus Snape arrived at Malfoy Manor alone. In the book, he arrives with Corban Yaxley.