Continuity mistake: When Sam is in his bedroom, after he finds the Cube sliver it falls and dramatically burns a hole through the floor into the kitchen. But Sam's bedroom is over the living room (there is nothing on the ground floor below Sam's elevated bathroom, and in the first movie Jazz hides in this open space), and the kitchen is actually located between the den and dining room, at the other end of the house. If they were to follow the actual floor plan of the house, the Cube sliver would have landed in the area of the piano in the living room, but where would the fun have been in that? (00:12:30)Super Grover
Continuity mistake: During the paper cut scene, when Bella is thrown against the table, there are 5 vases of flowers and 3 sets of candles. After she hits the table she lands against one of the vases and knocks the 2nd one to the floor, but the next shot shows only one vase left upright. (00:14:50)stareide
Continuity mistake: In the scene where Parker is shown playing golf on the indoor golf course in RDA, the first time he hits the ball, there are two other balls lying on the course side by side. In the next shot, two are distant apart and in the shot after that, they are in their original position. (00:12:15)
Other mistake: When Marcus, Kyle and Star are at the petrol station, a flying HK and the giant Harvester robot are able to appear just outside without making any kind of sound. In every other scene of the Harvester and the HKs however, they both make an incredible amount of noise. (00:37:40)GalahadFairlight
Factual error: In the poster shot and in the film, the wave from the Atlantic carrying the carrier JFK into a collision with the White House comes crashing in from the west because the south portico of the White House is seen. The Atlantic Ocean is east of Washington, so the wave should come from the other direction. And even a wave coming from the east could not have made the JFK (CV-67) crash into the White House because the carrier was retired in 2005 and is berthed in Philadelphia, which is northeast of Washington DC.
Plot hole: Inmediately after Jamie Foxx finds the bomb in the city hall, and he says, "We don't tell the mayor anything", we see Gerard Butler arriving to his property next to the prison, and finally he enters his jail cell. So, in the time between Gerard Butler's arrival to the property and his entrance to the jail cell, Jamie Foxx thought about a plan, picked up the bomb, passed through the traffic and security checkpoints, talked to the warden to get access to the prison, entered solitary, handcuffed the bomb, and still had time to wait for Gerard Butler's arrival.
Continuity mistake: When the house first becomes detaches from its foundation and becomes airborne, Russell is nowhere to be seen, although every angle of the house is shown, including underneath, the front porch and the back porch. He knocks on the door and tells Carl he chased a "snipe" under the porch - but he cannot be seen after liftoff and prior to knocking. The same thing happens near the end, when Dug claims to have hidden under the porch.MovieFan612
Continuity mistake: In the dormitory, when lovestruck Ron is going gaga over Romilda, he is wearing a brown sleeveless tee shirt and its tan trim has many holes. When Harry brings Ron to Slughorn, Ron is still wearing that tee shirt, but now some of the holes are gone and the rest of the holes have changed position. (01:26:50)Super Grover
Other mistake: At 1:39:14 the bomb arms, 32 seconds later at 1:39:46 (two seconds after it should have blown up) Dan and Molly jump from the helicopter. Then 10 secs later at 1:39:56, the plane FINALLY blows up after giving them those extra 12 secs to jump and conveniently make it to the pool below.vejay25