The Harry Potter books span seven books and contain well over four thousand pages full of a vast array of wizards, witches, muggles, and magical creatures. As such it would have been impossible for all of the many characters to be included in the films.
Whilst most of the characters missing from the Harry Potter movies were of little importance, perhaps only being mentioned a few times and only included to add color, there are a handful of fascinating book characters who played an important role in the main plot that movie-only fans are certainly missing out on.
7 Phineas Nigellus Black
Phineas Nigellus Black was a former headteacher of Hogwarts and as such earned himself a spot on the headteacher's office wall as a portrait. However, as a member of the House of Black, Phineas also had a portrait at 12 Grimmauld Place and could flit between the two.
This unique line of contact came in extraordinarily useful for Dumbledore and the Order of the Phoenix, and later Hermione would take his portrait with them to spy on new headmaster Severus Snape, who in turn was able to spy on them, though for their advantage. Other than playing the role of messenger in the plot, Phineas and his sharp, albeit often cruel, tongue provided plenty of wit and humor in the latter books.
6 Winky the House-elf
Although in the films it is the House-elf Kreacher who first provides a stark contrast to the lovable Dobby, The Goblet of Fire book actually features a female House-elf Winky who quietly acts as an important piece in the puzzle. Early on Winky is accused of stealing a wand and casting the Dark Mark, which to her horror she is freed and dismissed for by Barty Crouch Snr.
Readers and Harry then see the Hogwarts kitchens for the first time, where all the House-elves are more than happy to provide food and service; that is all apart from Winky who is sad, drinking, and constantly lamenting her lost family. All of this helped inspire Hermione to form S.P.E.W. (The Society for the Promotion of Elfish Welfare). Later in the book Winky helps reveal what was really going on with the Crouch family and in turn the main plot.
5 The Gaunts
Some of the best moments from Harry Potter and the Half-Blood Prince are the frequent journeys into Voldemort's past that Harry and Dumbledore take via the Pensieve. While some of these scenes make it into the movie to great effect, by skipping out a Magical Law Enforcer's memory, film fans unfortunately miss out on meeting the Gaunt family who are full of character.
The Gaunts are Voldemort's maternal family with Merope going on to become his mother by using magic to entrap a muggle called Tom Riddle. Despite this heinous crime, it is her brother and father and the abuse she suffers from them, that shocks readers and Harry most. As proud descendants of Salazar Slytherin, all of them speak Parseltongue and Morfin uses his in cruel ways. The father Marvolo, however, is probably the worst of the lot.
4 Peeves
For anyone who has read the books or even been lucky enough to attend Hogwarts themselves, Peeves the Poltergeist is a constant nuisance whose sole purpose appears to be the annoyance of students, teachers, and in particular the current caretaker Argus Filch. Taking glee in causing chaos and making students late to class Peeves is everywhere throughout all of the books and often has small instances of impact on the plot.
While Harry, unfortunately, finds himself on the wrong end of the Poltergeist's teasing songs more than once, there are also wholesome moments especially in The Order of the Phoenix when Peeves unites with the rest of the school against Dolores Umbridge. Best of all was when Peeves saluted Fred and George for their efforts towards mischief and the downfall of Umbridge. Despite not making it into the movies, Peeves will feature in Hogwarts Legacy​​​​.
3 Neville's Parents
Frank and Alice Longbottom are two of the bravest characters throughout the entire Harry Potter series, and it is sad that they were only mentioned and seen in a picture in the films. In the books, Harry learns of the former Aurors' tragic fates by viewing the memory of a trial involving Bellatrix Lestrange and Barty Crouch Snr for the torture of the Longbottoms.
Harry then has to hold onto this knowledge until he, Ron, Hermione, and Ginny happen to meet Neville and his parents at St. Mungo's Hospital. The scene is one of the most touching in the entire series and reaches a tearful crescendo when Alice hands her son a sweet wrapper, which Neville subtly pockets. As mere shadows of their former selves, it would have been a great way for the films to show just how dangerous magic can be.
2 Ludo Bagman
Ludo Bagman is an eccentric wizard who plays an important role throughout the entirety of The Goblet of Fire book. Over the course of the book, Ludo transitions from an over-excited former Quidditch Beater, who as Head of the Department of Magical Games and Sports is hosting the Quidditch World Cup and Triwizard Tournament, to a shady and ever more desperate red herring.
With the Weasley twins embroiled in their own problems with Mr. Bagman, his constant attempts to help Harry with Triwizard tasks, and even a Pensieve scene featuring his trial for apparently passing information to Death Eaters, it is easy to see how film watchers missed out on this Wimbourne Wasps legend.
1 Charlie Weasley
Although the second eldest of the Weasley brood was mentioned plenty of times and technically appeared in a family photo from Egypt in Harry Potter and the Prisoner of Azkaban, Charlie Weasley was unfortunately omitted from all eight films. In the books, Harry meets Charlie before the Quidditch World Cup, as well as during the Triwizard tournament as he has brought the dragons over. He also appears at the end of the Battle of Hogwarts with other reinforcements.
As a famously proficient seeker who could have gone on to play Quidditch for England and a wizard whose job revolves around dragons, it is easy to see why he is in contention for the coolest Weasley, and why it is a shame he didn't make it onto the big screen. Thankfully for fans who need more Charlie Weasley in their life, he plays an important role in the mobile game Harry Potter Hogwarts Legacy which starts in 1984, the year Charlie started his own Hogwarts journey.