There are quite a number of those in the story.
Before Hogwarts
- In 1985, during the summit of the International Confederation of Wizards, MACUSA are said to still be in hot water over the previous year's ghost invasion of New York, "especially since their Obliviators had messed up and barely managed to save the situation by planting the idea that the four men who battled and captured the ghosts without any magic were frauds."
- After Ron's reading improves through his interest in muggle comics, reference is made to him reading Zatanna, The Flash, Batman and Crisis on Infinite Earths, while actively dismissing his past wizarding comics.
- When Harry first learns about Bill's job as a curse-breaker, he compares Bill to Indiana Jones.
- Funny enough, Bill later on does start to wear an outfit like Indiana Jones due to being inspired by the films. The others make various jokes about it.
- The Evanses take the Weasleys to see several films in the cinema.
- They watch The Little Mermaid, and Harry suggests after the film that Ron and Ginny might enjoy seeing more of muggles' views on magic in Sleeping Beauty and The Sword in the Stone, especially as the latter features Merlin.
- They also watch Disney's Aladdin. When talking about the film and how hammy Jafar was, Ginny mentions that there was a Persian dark lord like that called Abdul Alhazred. That man is from the Cthulhu Mythos of H. P. Lovecraft, where he is the author of the Necronomicon.
- The finale of the chess tournament in which Ron participates, in its surroundings and the moves done, is modeled directly after the chess tournament scene in From Russia with Love. Also, his opponent's last name is "White", a reference to the James Bond villain Mr. White.
- Harry and Dudley's gym teacher Mr. Foster is partly inspired by Mr. Buzzcut from Beavis and Butt-Head.
Year 1
- By the author's own admission, he got the idea of how Percy manages to kill the troll with a massive accellerated lance from the episode Museum Piece in the Star Trek video game Judgment Rites, where such a lance is used to blast open a door.
Year 2
- When Mark Evans meets Dobby, he compares the house-elf to Gollum.
- After re-potting Mandrakes for their first second-year Herbology lesson, Hermione observes that first-year Herbology was more like working in a Muggle garden but this year seems more like Little Shop of Horrors.
- When Dudley learns that Voldemort's still alive, he compares what he's heard of Voldemort's current condition to a combination of Adolf Hitler and Freddy Krueger.
Year 3
- When Luna looks for the Divination classroom, she is warned to stay away from the portrait of Catweazle
, by another portrait, together with a short account how weird the man had become in life, talking about strange things after having vanished for some time. It perfectly matches the events of the series.
Year 4
- Ron's opponent in the national chess tournament in the summer after their third year is Stephanie Brown.
- Non-canon students from the other two Triwizard schools come from other franchises.
- At Beauxbatons, students are from Miraculous Ladybug. Fleur's best friends are Sabrina Raincomprix and Marc Anciel, while Chloé Bourgeois, Marinette Dupain-Cheng and Adrien Agreste are fellow students.
- At Durmstrang, those students are from the X-Men. That includes Pyotr Rasputin, Illyana Rasputin, Pietro Maximoff and Wanda Maximoff.
- Krum's comment about there not being enough space in Karkaroff's heart for anyone except for Karkaroff plays upon a line in The Hunt for Red October, where Captain Ramius says virtually the same thing about Captain Tupolev.
- During the first Triwizard task, Dudley considers the whole thing to be like a real-life adaptation of American Gladiators.
- Voldemort's final sentence to Crabbe Sr and Goyle Sr before torturing them in Chapter 48 brings to mind Darkseid's similar sentence to Kalibak in "Father's Day".
- When Snape is informed that a Death Eater he doesn't recognise is the supposedly dead Barty Crouch Jr., Crouch claims that he "spontaneously regenerated", an obvious shout-out to the most famous role of the actor who played Crouch in the films.
Year 5
- The MI-X members the Six and their families meet are named Mr. Clifton and Mr. Morden.
- The scene between Voldemort and Nagini at the beginning of Year 5 is modeled after King John and Sir Hiss' scene in Robin Hood (1973).
- When Snape gives his speech on the Dark Arts, he notes that the Dark Arts are very seductive. Harry internally name checks the Dark Side in Star Wars - being faster and easier, but more addictive.
- Pansy threatens Millicent with the words "Oh, better be careful what you do, Bulstrode, or one morning you could wake up next to a horse head.". That plays at a famous scene in The Godfather.
- A message delivered to Umbridge and her followers during a morning feast is clearly taken from Batman: Year One when he made a declaration of intent to Gotham's mobsters early in his career.
- According to the author, the scene where Crabbe and Goyle are cursed to have ape faces plays upon an episode of Adventures of the Gummi Bears, where Igthorn at the end is cursed by an annoyed sorcerer to have an ape face.
- When Dudley's Patronus turns out to be a wild boar, he makes it clear he doesn't want to hear Asterix jokes.
Year 6
- Dudley and Millicent (with the latter's cousin chaperoning) watch The Rock during a date.
- Hermione thinks that Voldemort's idea of society resembles Animal Farm, even dropping "All animals are equal, but some are more equal than others".
- During a day of relaxation at the Burrow, Luna teaches Harry Fizzbin.
- When Harry and Ginny explore each other intimately, Ginny remarks when seeing how eager Harry and his manhood are, that he looks ready to explode at any moment. Harry then replies "And don't worry. This bomb's for loving after all." This plays upon the song Sex Bomb from Tom Jones.
