Continuity mistake: Every time Barry is wearing the Flash suit the mask fits perfectly, but when he takes it off the size increases noticeably.
Continuity mistake: In episode 2.09 of related show "Arrow," during the day the particle accelerator is activated, Barry spends his time with Oliver, Felicity, and Diggle in Starling City. He arrives back in Central City just in time to see the particle accelerator activated, and he is in his lab because he was too late and missed the line at S.T.A.R. Labs. In episode 101 of "The Flash," Barry was never in Starling City during the day the particle accelerator was activated, and he and Iris actually attended the event. (00:02:10 - 00:11:30)
Continuity mistake: At the facility test while Barry is about to run the sun changes between shots.
Things You Can't Outrun - S1-E3
Continuity mistake: As Barry is going up the stairs in the police station and says he doesn't want a museum dedicated to him, a man and a woman are walking down the stairs. However, a second later, the shot has changed and the man is now a different person and the woman has gone completely.
Going Rogue - S1-E4
Continuity mistake: When Captain Cold shots Joe with the ice gun, he hits Flash instead, in the left side of his abs, but in the next shot the ice switches sides.
Power Outage - S1-E7
Continuity mistake: Barry examines the charred corpse in the morning, telling Joe and Eddie he hopes they skipped breakfast. He goes to Star and Cisco does facial reconstruction. They get the alert about the power plant, and when Barry arrives, it's nighttime.
Continuity mistake: As the detectives are talking to their captain about the bank robbery, in a shot from behind the captain he takes his hands off his food and clasps them in front of him. The shot cuts to his front as he starts talking, and he moves his hands and clasps them again.
Fast Enough - S1-E23
Continuity mistake: When Eddie is dead, his eyes are closed. But in a close up shot of him, his eyes are opened. Then when he's being pulled into the wormhole, they're closed again.
Fast Enough - S1-E23
Continuity mistake: When Ronnie and Caitlin are getting married the sun changes between shots.
Continuity mistake: After Barry draws Vandal Savage to show the team what he looks like, he tucks the pencil being his ear. Several shots later the pencil disappears. (00:11:45)
Trajectory - S2-E16
Continuity mistake: At the very beginning when Cisco throws a rock to the river beside Barry, the sun changes between shots.
The Present - S3-E9
Continuity mistake: When The Flash reveals to Julian that he's Barry, he pulls back his cowl, leaving it around his neck. But in shots of Barry's back after Julian says his sister died, the cowl is gone. The cowl is around his neck in all the other shots.
Continuity mistake: When Barry and Kara get shot outside the bar, at first the spot of blood on Barry's shirt is bigger than when Iris and Mon-El later get to the scene. (00:34:00)
Continuity mistake: Near the end when Iris and Joe are talking, Iris sits with her elbow on the couch and her head against her hand. In the next shot, her forearm is resting on the couch, and her hand is hanging down, away from her head.
Continuity mistake: The explanation that Cisco draws about the endless cycle changes in between shots, not counting the added words "past", present", and "future" (which he could have written when off camera, not that it would make sense to do so since he already explained what was past, present, and future). Where the loop crosses itself is higher up as well as the "FF + TR" being different.
Continuity mistake: When Iris covers herself with the blanket, the blanket is off her left shoulder, and you see her dress strap. Later the blanket is fully covering her shoulder. The blanket changes a few more times in later shots.
Continuity mistake: When Cisco opens up a portal, Caitlin and Dominic are next to it and seen moving towards it, with Ralph standing in front of the group (as if he's covering them). In the next shot, Caitlin and Dominic are going through the portal followed by Cisco, but Ralph is nowhere to be seen as he's already entered the portal. There should be no way for him to completely enter the portal first.
Continuity mistake: When Joe and Iris are going to talk to Matthew Kim, Iris is already wearing the suit that Cisco later makes for her, she just wears it open the first time and closed the second time. (00:13:41 - 00:29:50)
Suggested correction: She is wearing the jacket when speaking with Matthew Kim because it is her jacket. When Cisco has her new outfit in the suit bag, he said something to the effect of "I had to make do," meaning that it was short notice and he could not make her a suit like he did for other speedsters. She is essentially wearing regular clothes with a mask, and her jacket was part of that outfit. Quite frankly, all the clothes could have been hers, but we know the jacket is.
Not only that, but in the scene before, we see the jacket hanging over her chair. So just something she wore that day.
News Flash - S5-E4
Continuity mistake: When Iris and Barry are on the baseball field beside the bench the sun changes between shots.
The Last Temptation of Barry Allen, Pt. 2 - S6-E8
Continuity mistake: When Barry was infected by Rosso his infected fingers and nails tore through the fingertips of his gloves. When he is healed from the infection the fingertips in his gloves are no longer torn. (00:30:18)
