The One With All The Wedding Dresses - S4-E20
Continuity mistake: When Chandler is telling Monica and Phoebe about the girl who picked him over Joey, look behind him and you will see Gunther nodding to a lady in a denim jacket. In the next shot, the woman walks up to the counter again, and again Gunther is nodding at her. (00:17:00)
The One Without The Ski Trip - S3-E17
Continuity mistake: When Chandler tells Rachel to "shut up; you're not my mom," Joey has both hands on the bottom of the Chinese food carton. In the next shot his right hand is on top of the box. (00:05:30)
The One With Ross's Sandwich - S5-E9
Continuity mistake: In the second scene with Phoebe and Rachel in the night class, when the camera looks over Rachel's shoulder, she has "Jane Eyre" in her hand face up, but when the angle switches to front view, she has nearly placed the book on the desk. (00:13:20)
The One With Rachel's Crush - S4-E13
Audio problem: In the scene where Rachel walks into the guy's new apartment and they start talking about Joshua, it cuts to a shot of her in profile as she says "It's just so frustrating". Her mouth doesn't move as she says the words. (00:09:40)
The One Where Estelle Dies - S10-E15
Continuity mistake: When Chandler says his boss is getting him a new lamp in his cubicle, his arm is over the back of the chair, in the immediate next shot it is moved and then back again. (00:00:50)
The One With The Late Thanksgiving - S10-E8
Continuity mistake: When Rachel and Phoebe are talking in the Baby Beauty Contest and Rachel is holding Emma, Emma's head instantly changes position between shots several times, often going through 180 degrees. Clearly they couldn't get her to do the scene in one take and therefore the editing suffers. (00:07:05)
Factual error: This mistake is from series 6 onwards, with Ross' new apartment: There is an impossibility with Ross' kitchen, but not all of the time. It depends on the layout of the hallway outside his apartment. If the hallway continues along for a bit before going left or right, then the kitchen should stick out. However, when the hallway is a dead end, the kitchen fits ok.
The One with the Thumb - S1-E3
Continuity mistake: When Chandler says he won't quit smoking, he holds his hands out. In the next shot, they are lowered between his legs. (00:06:00)
The One With Ross's Wedding, part 1 - S4-E23
Continuity mistake: When Monica, Ross and Emily are going to see the church, Emily's hands move between shots with no time to do so. (00:05:30)
The One Where Ross And Rachel Take A Break - S3-E15
Continuity mistake: When Cloe hands Chandler and Joey the flier, it goes from flat to folded to flat in 2 camera cuts with no time to do it. (00:03:15)
The One Where Rachel Quits - S3-E10
Continuity mistake: At the start of the scene in which Ross breaks the little girl's leg, we can see that the stairs are just separated by railings. Later in that scene, when Ross and Chandler start walking up the stairs, there are walls on both sides of them. (00:01:40)
Suggested correction: This isn't completely true. In the first shot, we see railing in the middle, as shown in the screenshot. Then, the shot changes to upstairs, looking down, and we can see the wall, as shown in the bottom picture. However, at the end of the wall, it goes into the railings, which is visible just as the pair start to climb the stairs. A screenshot of this can be seen here: https://ibb.co/bmZ8xTc, making it easier to understand.
The problem with the screenshot is the right side is circled to show there's no railing, but the railing is on the left side (to the character's right), but Chandler is blocking the view of the railing. Ssiscool's screenshot is before Chandler starts to walk up the stairs, which is why it's seen.
The One Where Rachel Quits - S3-E10
Continuity mistake: The gang enters Monica's apartment and it is full of dead Christmas trees. After everybody has entered the apartment we see that the apartment door is shut; the shot then changes to the gang around the sofa, but in the next shot when Rachel answers the phone we can see behind her that the door is open. (00:19:00)
The One Where Chandler Crosses The Line - S4-E7
Continuity mistake: When Chandler is showing Joey all of the new stuff in the apartment, the cuff on his right sleeve keeps going from messy to neat between shots. (00:13:45)
The One With The Hypnosis Tape - S3-E18
Continuity mistake: When Frank Jr is sitting in front of the TV while Davey and Goliath is on, his hand is along the edge of the TV set; however when Phoebe walks in, his arm is straight out. Then when Mrs Knight comes in, his head is straight down and the arm is back along the edge. (00:15:15)
The One With Phoebe's Ex-Partner - S3-E14
Continuity mistake: When Monica comes in and asks Chandler if she can borrow some milk, Chandler is reading a paper that is flat on the bar. In the next shot he is holding it folded, then he lays it on the counter, and suddenly it is in his hands again. (00:14:20)
The One With Monica and Chandler's Wedding, Part 1 - S7-E23
Continuity mistake: At the rehearsal dinner when Chandler loosens his tie and unbuttons his collar, the tie changes its appearance in the following shots from being tighter to looser several times. (00:09:30)
The One with the Dozen Lasagnas - S1-E12
Continuity mistake: In The One Where Ross Finds Out he's having a boy (series 1), just before Rachel lets it slip, she is sitting on the edge of a chair eating a cookie. Watch her dress, it changes back and forth from being undone from the waist up, to only having two buttons open at the top. (00:19:55)
The One With Rachel's New Dress - S4-E18
Continuity mistake: In The One With Rachel's New Dress, she's in her underwear on the sofa when Joshua comes in. In wide shots focusing on Joshua she's quite laid back, but in close shots of her she's sitting more upright. Worse than that, her legs are crossed, but uncross in the shot of his parents coming in, only to re-cross in the next shot when she gasps. (00:14:35)
The One with the Stoned Guy - S1-E15
Continuity mistake: When Chandler says he can't work out what he wants to do working at his job, he is standing behind the sofa. In the next shot, he is in front of the sofa sitting down. (00:02:50)
The One with the Stoned Guy - S1-E15
Continuity mistake: Just before Chandler tells everyone he quit, he holds out both hands in front of him. In the next shot, his left hand is by his side. (00:02:05)
