Airplane!: Ted and Elaine (meeting in the bar, in the Peace Corps, in the hospital, rolling on the beach), Ted's war memories. These can get ridiculous... The reactions to them can get a bit more ridiculous.
All About E: E's prior relationship with Trish is continually shown by these during the film.
Apparitional: A number of sepia-toned flashbacks occur in the movie, showing events in the location's past that lead to their hauntings.
August In The City: After her daughter Ana comes home with a girlfriend, August remembers how she'd dated a woman named Clem many years before, which makes up much of the film.
Batman Begins uses the non-congruous Nolan style jump. First, we go back and forth between Bruce in a Chinese prison and being trained by the League of Shadows to a young Bruce being rescued from a well by his father and watching his parents' death. When Ra's asks Bruce what inspired his travels, another lengthy flashback is used that documents Bruce witnessing Joe Chill's death and his encounter with Carmine Falcone.
Bethany: Claire starts having flashbacks of her childhood soon after moving into her old home. They're mainly of her and her rather controlling, abusive mother.
Billy Club (2013): The movie is peppered with flashbacks of the protagonists' childhoods in the Wisconsin Blue Birds Little League team. It also contains a few to Billy's time in the mental hospital after he killed two of his teammates and the coach.
Blazing Saddles. While Sheriff Bart and Jim are talking, Sheriff Bart tells Jim about how his parents came out West in a covered wagon and dealt with hostile Indians.
Blind Horizon: Recurring and frequent ones occur with the main character, giving clues to his past.
Capps Crossing: The film is peppered with a few flashbacks. One happens regarding a murder that occurred five years prior. The rest are about the end of David's relationship with his then-girlfriend, and how he killed her father when he found her dead, accusing him of doing it.
Citizen Kane tells the story of someone who died at the beginning of the film, so a high percentage of its running time is Flashbacks.
Clownface: Owen has a flashback while he recounts playing with a stick like it was a sword when he was a kid, and sees Clownface.
Cruel and Unusual: The rooms Edgar and the other people enter trigger this, making them relive what they did to be condemned.
Cut to the Chase: A number of these show Max's past with his sister Izzy, to fill in things.
At the eight-year anniversary of Harvey Dent's death, Gordon flashes back to a raving Harvey threatening to kill Gordon's son while deciding whether or not to reveal Harvey's crimes.
After a failed attempt to escape Bane's pit, Bruce briefly dreams about being rescued by his father from the well on the grounds of Wayne Mansion again.
Bruce flashes back to Ra's talking about his family in Batman Begins.
In the finale, Gordon flashes back to putting Thomas Wayne's coat around young Bruce decades earlier.
In Daylight (2013), Ray has many flashbacks to his relationship with Rosita, the prostitute he was accused of murdering.
Dementia (1955): Done in a bizarre scene that fits the film's Mind Screw surrealism. The woman sees her parents' tombstones in a cemetery, and is thrown into a flashback that actually takes place in the cemetery. Her father lies on a bed that is sitting there between the graves; he is shown to be an abusive drunk. Her mother is then shown lying on a couch, also in the graveyard. The father sees someone else's cigar next to the couch, realizes the mother has been cheating on him, and then shoots her. The woman that is the film's protagonist then kills her father by stabbing him in the back.
El Camino: Around a third of the film consists of flashbacks that take place throughout the Breaking Bad timeline.
Exotica: One shown in parts through the film and another at the end of the film.
Fast Color: Ruth has fragments of one that later gets shown in full showing that her abilities accidentally had caused a flood in which her daughter Lila was almost drowned.
Fearless uses flashbacks extensively, showing the lives of characters affected by a plane crash intercut with flashbacks to the crash itself.
Fire in the Sky: The flashback at the end is very important. Travis Walton disappeared at the beginning of the film and the police suspected Allan Dallas of murdering him. About half the film is trying to prove Dallas to be the murderer but even after Walton reappears five days later, he's in no condition to tell anyone what happened. His flashback reveals the mystery.
In A Fistful of Dynamite, the main protagonist has flashbacks from his better days back in Ireland, with his friend and an unnamed woman featuring in brief scenes featuring no dialogue. Later we see the reason he left Ireland in the same style.
In The Force Awakens, Rey receives a few of these after touching Anakin's lightsaber for the first time. It includes the destruction of Luke's attempted Jedi Order by the Knights of Ren, and Rey herself being left on Jakku as a child.
Young Anna and Elsa being told a story about the Enchanted Forest by their parents.
The opening shows what happened in the Enchanted Forest, showing Prince Agnarr joining Arendelle's forces in an expedition into the woods, a group of Northuldrans in the forest, and a war breaking out between Arendelle and Northuldra in the woods only for the mist to rise up and cut off the forest from the rest of the world.
Each of the killers has a flashback showing the crimes they committed that got them locked up at the Statesville Mental Hospital.
There are more flashbacks to Manual Dyer burning a member of his flock that reveal that that member was Sheriff Kate's mother, and that Eileen was present for it because she's Manual Dyer's daughter.
Ghost Lab (2021): After Dr. Wee is made into a believer of ghosts, Dr. Gla tells him about how he saw his father's ghost as a kid via flashback.
John Carpenter's film Ghosts of Mars use extensive flashbacks that get more and more convoluted as the film goes on. The film is framed as one character telling the events to her superiors later; but every time she or another character meets up with someone new on the planet, that person explains whats been happening to them in their own flashback, and this repeats itself when they meet new people. This eventually devolves into the viewer watching a flashback within a flashback within a flashback within a flashback. Quite jarring if you let yourself become aware of it. Kudos to the character speaking to her superiors, though, who could remember everything she heard fourth-hand verbatim.
Quite a few appear in G.I. Joe: The Rise of Cobra, detailing the relationships and origins of basically everyone.
Grandmother's Farm 2: Khalid's Nightmare Sequence near the start of the movie is flashbacks to the girls he met in the previous movie, and of taking Noora back to the farm. There are some other flashbacks later on in the movie.
Hayride: A couple of flashbacks occur when Morgan tells the story of Ol' Pitchfork to his family and Amanda.
Hayride 2 has flashbacks from the events of the previous movie (in sepia tone), and another (not in sepia tone) of Morgan telling Steven and Corey about how to face their fears.
Jane Got a Gun: Several of these show Jane, Dan and Bill's backstory.
In Jaws: The Revenge Ellen has several flashbacks throughout the movie, although there is no way the majority of the scenes could be in her memories as she wasn't present for many of the events.
In The Last Witch Hunter, the events that happened eight hundred years prior are key to solving the present-day puzzle, so Kaulder has multiple flashbacks to that time, as well as his happy days with his family.
The 1956 melodrama The Locket bears the distinction of having a flashback within a flashback within a flashback within a flashback.
The Lodgers flashes back to a younger Edward witnessing his parents fulfill the final edict of the family curse by drowning themselves (or perhaps the father drowning both the mother and himself) in a pond.
In the beginning of Lola Rennt, Manni's predicament is shown in flashback as he describes it. Then there are numerous flash-forwards as Lola encounters various characters, in rapid-fire montages showing their futures.
Main Street Meats: There are a number of flashbacks shown over the course of the movie detailing the three siblings' childhood with Ma.
Mako (2021): Late in the movie, Gharam has one about how she left her youngest sibling in their room on the Salem Express when it sunk.
Inverted in Memento, which flashes forward at intervals until the movie ends in the middle of the story.
Nutcracker Massacre: While Dimitri is telling the tale of the German soldier from the 19th century, the movie flashes back to the events as they're being described.
None Shall Escape is a 1944 film about a trial against the fictional Nazi officer Wilhelm Grimm following the end of the then-ongoing second world war which is told via flashbacks from the points of view of the witnesses at the trial. There are three in total (corresponding to the three acts of the movie): the first one by Father Warecki takes place in 1919 right after the end of WWI and deals with how Wilhelm came to be an outcast in his hometown of Lidzbark (in what used to be the German Empire but is now Poland) before he left for Germany, the next one by Karl takes place in 1923 right before and after the Beer Hall Putsch before skipping ahead to 1929 and then to 1934 after the Night of the Long Knives and tells the story of Grimm's rise within the Nazi Party, and the last one by Marja takes place during WWII and shows his return to Lidzbark as Reichskommissar and the oppression of the populace there.
Passage to Marseille was a movie in which a reporter comes to an air base to interview a Free French officer who starts telling the story of one of his men (Humphrey Bogart). Flashback to the man being recovered at sea by a ship along with four others. It is revealed that they are escaped prisoners. Flashback to them planning to escape in order to join the fight against the Germans and saying why they absolutely...
Patient Zero (2018): A few flashbacks occur in the movie. They mainly recount Morgan's life before the outbreak. The Professor gets a couple as well. They recall what he did when the outbreak reached his school, and how he became infected. They also recall how he killed his family under the influence of the infection.
Rashomon is largely told through flashbacks. There are even nested flashbacks. It's so famous for this, it became the Trope Namer for "Rashomon"-Style.
Hoodwinked! was based on Rashomon and uses the same thing. In fact, close to half of the film is flashbacks as the characters are interviewed by Nicky Flippers to explain how they ended up in Granny's house.
Rise of the Scarecrows used a sepia-toned flashback of the origins of the three Scary Scarecrows out in the woods. They were a bunch of construction workers Sheriff Howard killed out there, who came Back from the Dead. Mike states that a likely reason for why they're scarecrows is that the sheriff dressed them up that way as a joke before he killed them.
Mission to Mars ends with Jim having rapid flashbacks of his late wife and all his friends, as he is preparing to leave for another galaxy to meet the progenitors of humans.
Pope John Paul II begins with the assassination attempt in 1981, then flashes back to tell the story of the Pope as a young man, before eventually catching up and continuing on to his death in 2005.
Saving Private Ryan plays around with its flashback a bit. It starts with an Age Cut into the flashback, except the old man in the graveyard is Private Ryan, not Captain Miller seen in the landing craft. Ryan isn't in the flashback at all until the final battle, and couldn't have remembered everything shown first-hand. (It is, however, possible that the story is relayed to Ryan through Upham).
The Saw films do this extensively as a means of explaining the convoluted plots and building character development, even when many of the main characters are dead in the 'current' timeline.
Scarred: Sometimes, the film flashes back to the scene where Jonah Kandie's father cut up his son's face with a knife, and then shot his mother. The one at the end even shows him shooting himself.
Shaolin Soccer features a unique subversion: While Sing is trying to convince an old soccer coach of the value of Kung Fu, there are flashbacks to an ancient master performing techniques described, a master played by the same actor as the coach. The coach interrupts the last flashback by pulling off the old master's costume and stepping out of the character.
In Silent Night, Deadly Night Part 2, the whole beginning is a flashback to the first movie even though there is no way that Ricky could've remembered any of the events depicted except for the last one because he was either a baby or wasn't present.
Jay in Sky Blue has a flashback to when Shua showed her the blue sky; Shua later has one to a few minutes later, showing why he was exiled. Later still, Cade has a flashback to the same event, where it turns out he framed Shua for his own action.
Sorry, Wrong Number: As Leona learns about what Henry’s been up to, there are various flashbacks of other characters and their interactions with him. Includes a Flashback Within a Flashback.
Space Chimps 2: Zartog Strikes Back: While Zartog is trying to communicate with the humans, he does a bad impression of Ham. Ham shows up behind him and says Piddles the Clown does a better impression of him than that... cut to Piddles imitating monkey chatter.
Strippers Vs. Werewolves: We're treated to one when Raven recounts how her boyfriend left her, feeling he wasn't good enough for her.
Trespass (2011) has several flashbacks explaining the events leading up to the home-invasion robbery.
In Turning Red, during the red moon ritual, Mei relives numerous memories from her time as the panda including moments only previously seen in the form of camcorder footage her father showed her in the previous scene.
Waves '98: In one scene Omar closes his eyes, and superimposed over his animated face is a live-action shot of a boy swinging in a swing, presumably a childhood memory of Omar's.
What Keeps You Alive: Jules experiences many of these, remembering happy moments in the past with her and Jackie. At the end, Jackie flashes back to her childhood killing a bear.
Zero Focus has a a flashback-within-a-flashback when Sachiko remembers Hisako remembering her relationship with Kenichi.
before skipping ahead to 1929 and then to 1934 after the Night of the Long Knives