Continuity mistake: When Scotty and Cooper leave for London, the airplane taking off has an engine on its tail. The very next shot is of a different airplane that has no engine on its tail. (00:19:10)
Visible crew/equipment: When Kelly bursts into the classroom and pulls the main character out of the chair there is a shot of them from behind as they leave. There you can see the battery pack on the back of the main characters pants. (00:59:00)
Continuity mistake: When Carter is splashed as the twins jump into the pool, only one side of his head/hair is wet. In the next shot, all of his hair is wet. (00:56:50)
Continuity mistake: When Jack first meets Maya and they are all having a drink at the bar, Maya is holding a cigarette. We can see she is holding the cigarette up near her face when the camera shows her from behind but is all of a sudden holding it near the bar counter in shots of her face. This continues until about halfway through the scene.
Continuity mistake: In a couple of close up head shots of Paul Bettany in the final match, the tag in his shirt is visible. In one shot the size of the t-shirt is L (large), in a later shot within the same scene it says M (medium).
Continuity mistake: When Chris is hitting the slot machine in the Casino, we see that the cover on the machine comes off, then the lights are off. But when the shot changes, the lights are on. (00:38:15)
Continuity mistake: When Gary is remembering at the start of the film the incident with his family and is looking at the picture in the mirror, you can see there are 4 people in it. The next shot when Gary is speaking with Spottswoode the picture (to the left) has changed to being just 2 people in the picture.
Continuity mistake: When Bobbi, Roger, and Jo break into Sarah's house, just as they hear the noises upstairs Roger's arms change from at his sides to crossed. (00:33:25)
Continuity mistake: When Viktor and Amelia are having dinner in the terminal, Enrique fills her glass very full. However, in the shots with only Amelia, the wine level changes to be significantly lower, though she never touches the glass. (01:26:00)
Continuity mistake: When Hiram, Juan and Kelly first see Old Fred's wagon in the distance, the white tarp on it is draped across it and down one side. When they arrive at it, it's draped differently. They also arrive at it from the side, when they were approaching from straight in front on it. (00:46:15)
Continuity mistake: In the scene when Harold and Kumar go into the girl's bathroom and hide in the middle stall, you can see all of the stall doors are closed. When the twins are standing at the mirror in the bathroom, you can see in the mirror that the stall door behind the twin in pink is open, and then it is closed again. (00:23:45)
Revealing mistake: When Alfie goes back to see Julie, he stands in the street, apparently looking towards the cafe, but we can see the cafe (and especially the building next to it with red awnings) in the distance behind him. (01:08:30)