The One With The Ball - S5-E21
Factual error: There is no way that a cop and a masseuse could have afforded an apartment in Brooklyn Heights, even in the '90s. (Brooklyn Heights was unaffordable in the '80s.) "Rent control" doesn't explain it either, as a vacant apartment - which is what they are looking for - would be raised to "market rate" if a rent-stabilized tenant moved out. This can't be written off as a character mistake: Gary is not naive or uninformed, and his accent makes clear that he is a New Yorker.
The One With Monica and Chandler's Wedding, Part 1 - S7-E23
Continuity mistake: When Monica and Chandler walk toward the middle of the room the camera cuts to Ross talking to his parents saying that he could kick Chandler's ass, Behind them are Monica and Chandler in a different place, listening and laughing to Ross. (00:10:50)
Suggested correction: The shot is continuous. There is no continuity mistake.
The One With the Pediatrician - S9-E3
Continuity mistake: Ross' broken finger disappears overnight. It's broken in one scene, not broken in the next scene which takes place on the same or next day.
The One with the Boobies - S1-E13
Continuity mistake: When Joey's dad walks in and sees Ronnie, he shuts the door. However, as they go to leave to a hotel the door is open and Joey shuts it. (00:11:50)
The One With The Racecar Bed - S3-E7
Continuity mistake: When Monica and Rachel show Ben them banging their heads against the wooden beam in the kitchen, Phoebe is hovering on the phone in the background when she is supposed to be at the dentist's office. (00:14:13)
The One Where Nana Dies Twice - S1-E8
Continuity mistake: In Central Perk, Joey says "So, Chandler looks gay huh?" When he does his arms are not crossed. Camera cuts and they are. (00:08:30)
The One with the Blackout - S1-E7
Other mistake: Phoebe says she was last to know Monica had a crush on Joey when he moved in and Joey acts as though he never knew this. However, when we see him moving in a later episode, he knows Monica has a crush on him, and he is under the impression that Monica wants sex and so strips off in the living room while Monica is preparing some drinks for the pair. (00:13:10)
Suggested correction: I may understand the situation but please do correct me if I'm wrong. Basically in the flashback episode they saw each other in the hallway and smiled at each other. They would've both got the impression that the other one liked them. However, after the lemonade incident he would have then got the impression that he was wrong and Monica didn't actually like him. Finally, Joey heard that she did like him and got a bit confused and a bit happy at the same time.
The One with the Boobies - S1-E13
Visible crew/equipment: When Joey's mum pushes the sofa bed away, a crew member can be seen hiding behind the sofa. (00:17:00)
The One With The Donor - S9-E22
Continuity mistake: In the first scene in the coffee shop Emma is in a carriage beside Rachel. Later on when they come back to the coffee shop Rachel leaves and the baby carriage and the baby are nowhere to be seen.
The One With All The Cheesecakes - S7-E11
Continuity mistake: When Rachel and Chandler are out in the hall eating cheesecake off the floor, Chandler's piece is much closer to Rachel's piece than in the previous scene when Rachel slapped it out of Chandler's hand closer to the apartment doorway.
The One With The Memorial Service - S9-E17
Continuity mistake: In the beginning when Joey tries to spin the ball with his finger, it falls, hits the table and bounces to the background. In the very next shot it is seen falling behind Chandler on the couch.
The One In Vegas, Part 2 - S5-E24
Continuity mistake: When Monica and Chandler kiss under the table, as "Everybody Loves Somebody" plays, Monica is shown smiling. She then closes her mouth. In the next shot, she is smiling again without any time to do so.
The One With The Football - S3-E9
Character mistake: Ross tells Chandler to run a "post pattern to the left." (And Chandler quickly agrees.) In football, this is a type of passing play where Ross would hold on to the ball while Chandler runs straight down the field immediately after the snap, eventually veering diagonally to the left once he's a ways down field to receive a pass from Ross. The play that they actually run is completely different. It's a running play known as a sweep. (A toss sweep to be precise.) There is no possible way that anyone either making play calls or running them would ever confuse a post vs. a sweep. (00:10:10)
The One With All The Resolutions - S5-E11
Continuity mistake: Immediately when the opening scene starts, we hear from the crowd on the television that there is less than 60 seconds to midnight. However, 60 seconds later in the scene, the countdown still hasn't reached zero.
The One With Mac & C.H.E.E.S.E. - S6-E20
Continuity mistake: As Chandler is writing on the board to remind himself about Joey's audition, the door opens as he's writing "Joey", and there are a bunch of squiggly lines under the y. As Chandler is thinking back at that moment and it moves to present tense, he looks over to the board, and the squiggly lines are different.
The One With The Ball - S5-E21
Continuity mistake: When Rachel is outside the coffee shop trying to sell the cat, in between shots, it goes from a standing to sitting position multiple times.
The One Where They're Up All Night - S7-E12
Visible crew/equipment: Right after Tag wonders if he can see his apartment from there, when Ross says "wow, look at all the stars" a boom-mic is visible for a short amount of time.
The One with the Boobies - S1-E13
Continuity mistake: When they're all sitting together and having pizza, talking about parents, Rachel has no napkin. When she says: "Just think, in a couple of years we get to turn into them", a bunched up napkin appears beside her on the couch. After Chandler's remark it has disappeared again, then it appears and reappears again between shots. (00:21:10)
The One Where Emma Cries - S9-E2
Continuity mistake: When Chandler wakes up and spits out the balloons, his legs change between shots from being crossed to having one foot on the table and back, at least twice. (02:00:00)
The One with the Ick Factor - S1-E22
Revealing mistake: In the scene where they are in the coffee shop talking about Rachel's dream about Chandler. Rachel is carrying a coffee pot around then sits down. When she sits she puts her hand under the coffee pot, which would be extremely hot if it were real.
