Continuity mistake: In the first film, it is mentioned several times that Kevin is 8 years old. However, in this film it is stated that he is 10. When his parents are in the Miami airport security office, they say that he was left alone last Christmas. That would make him 9. Both films take place the same days, from about three days before Christmas until Christmas morning, so even if Kevin is born around Christmas time this is still a mistake.
Continuity mistake: The tiger bites the seat off the suitor's trousers, allowing the viewer to see his polka-heart boxers. When we see the tiger in the courtyard, he has a part of the same boxer shorts in his mouth. So if he bit off the seat of the trousers, shouldn't he have purple cloth in his mouth? (00:11:45)
Other mistake: Towards the end where they steal the chip, they are detected and about a million security guards are all running around, yet 30 seconds later, the only security guard is one man with a shotgun. What happened to their big army of security guards? (01:41:30 - 01:42:55)
Suggested correction: This isn't a mistake. Bishop had been directed to a part of the building where there weren't any security guards; this was shortly before one of the guards found their camera feed. The guy with the shotgun was the only person to head into that location. Unlikely maybe, but possible.
Continuity mistake: In the scene where Gabriel Byrne is dancing around the fire with the travellers, he is wearing a large leather coat. After the police come and go, he's no longer wearing the coat. In the same scene, it shifts from night to day quite quickly, too quickly to be a sunrise.
Visible crew/equipment: At the surrender of the fort, as the English are marching out, Monroe, says "The fort is yours, Monsieur." Right as he speaks, look between the two horses' heads. In the distant valley you can see what are either two tourist busses or perhaps mobile catering vans. (01:05:40)
Factual error: The baby is expanded to approximately fifty times his height, width and girth but it's explicitly stated that he retains his orginal mass. This means he will have the same volume as one hundred and twenty five thousand babies of his original size, but will weigh the same as before he was enlarged! That child is going to weigh much less than the volume of air he displaces. He's going to float away.
Continuity mistake: At the beginning, there is a scene where Ben spills a carton of milk. He picks it up right away, but a split second later the scene changes, the milk is still lying down, and he puts it upright again. (00:06:25)
Factual error: When Nicole Kidman and Tom Cruise arrive in America, the year is 1892, but the flags being passed out at the pier have 50 stars on them. In 1892, there were 44 states.
Factual error: The Nina, Pinta, and Santa Maria are shown starting back for Spain at the end of the first voyage. In fact, the Santa Maria had wrecked by this time; the return voyage would be made only by the Nina and the Pinta.
Continuity mistake: During one scene, Mel Gibson is talking to the young boy through the treehouse door and holding the boy's jacket. The next scene, there is no jacket and then it magically reappears. (00:35:30)
Continuity mistake: When Bronx go to sleep intoxicated (the night the medicine man paints on her face) she is wearing a shirt and panties, but when she wakes up she is wearing a pair of jeans.
Continuity mistake: As Hampton's family leaves town for Happy World Land, the car's odometer approaches 100,000 miles and, at this point, Wade grabs a camcorder with his right hand and starts videotaping the event. But in the next shot however he's steering the car with both hands - and still operating the camcorder somehow. (00:05:50)
Plot hole: The Frying Dragon team wins the Breaking, Weapons, and Men's Fighting competitions, as well as coming in second place in the Women's Kata, yet they are still only tied for the lead in the end?
Continuity mistake: Peter Weller draws his automatic pistol and cocks it using the slide. He turns to the prisoner. The shot changes and as he walks behind the prisoner he cocks the gun again.
Continuity mistake: When Master Pan chases Li to a back area, a couple of guys stop to fight him to give Li a chance to get away. The one with short dreadlocks throws a jump spinning kick at him, and he Pan sends him flying into a ramp with his sword. Later, while Pan is fighting Eric Lee, there is a quick shot of that same guy sitting on the ramp very relaxed, then he vanishes entirely.