Continuity mistake: At the end of the film, the train flies off the track, through a wood-framed tunnel under construction, and then onto a city street. During the credits, as the shot is pulled back, there is no destroyed wood-framed tunnel. In fact, traffic is flowing normally in the background.
Visible crew/equipment: When Jack is talking to Howard from the pay-phone, you can see the boom microphone's reflection in the phone in several shots.
Revealing mistake: When Jack is fighting Dennis Hopper on the roof of the subway train, a peice of paper falls off one of them and then stays surprisingly still considering they're on a speeding subway train.
Revealing mistake: After Jack has taken command of "Tuneman"s car, in the wide shots of them chasing the bus you can tell it's not Keanu Reeves driving. The stunt driver has slightly longer hair in a more squared crew cut.
Continuity mistake: In the first part of the movie, it appears that the building is approximately 53 floors high, we can see this as when Keanu Reeves and Jeff Daniels go to the roof the label on the door is "ROOF/53". However, the service elevator seems to reach the top of the shaft after Dennis Hopper enters level 46 on the control panel. This is rather unfortunate, especially as the security console says that the elevator "serves floors GE-52". I wouldn't like to be in the elevator as it tries to go past level 46 to a higher floor such as 52.
Continuity mistake: When Dennis Hopper's shooting the shotgun through the lift roof, the number of holes doesn't match the number of blasts. He shoots once and a hole appears. We then see a close up of him and he shoots twice more, but when we cut to the ceiling after the third shot overall, there are only two holes in it. Doesn't seem likely he'd miss the roof at a range of 2 feet.
Continuity mistake: In the scene where Jack is fighting Dennis Hopper on the roof of the subway train we see Jack lying on the top of the train getting punched by Dennis. We briefly cut away, and then back to Jack and the corrugations on the train roof have rotated through ninety degrees.
Continuity mistake: When Jack is running across the street in downtown Los Angeles, in two different camera shots two different red cars are shown stopped in the same place to let him cross the street.
Continuity mistake: When Jack is chasing the bus on the freeway in the Jaguar, an overhead shot is shown of the bus with three cars around it, but in the next shot of the traffic, the road is full of traffic which is surrounding the bus, which is highlighted by Jack having to to swerve around the cars.
Plot hole: Jack has been using the phone he took from "Tune-Man" ever since getting in his car. Payne has been calling Jack on that same phone while he was on the bus, but Jack never gave him the number. How has Payne been calling him?
Factual error: According to the TV announcer, the bus went from the Santa Monica Freeway to Western Avenue to the 105 freeway. Two problems would have occurred. First, the Western Avenue exit from the SM freeway is way too narrow to safely make a turn at such high speed. Second, there is no onramp from Western Avenue to the 105 in any direction.
Revealing mistake: Before Jack rips the door off the Jaguar, he speeds ahead of the bus and then opens the driver's door at highway speed. At 50 MPH there would be a lot of air resistance, yet Jack opens the door effortlessly.