Anachronisms: The story on Donald Campbell in Sally Williamson's typewriter refers to Coniston as a "Cumbrian village". In 1966 Coniston was in the county of Lancashire. The county of Cumbria didn't come into existence until local government reorganisation in 1974. It was formed by merging the ancient counties of Cumberland and Westmoreland and taking the southern part of the Lake District from Lancashire.
Crew or equipment visible: After the "French restaurant" incident, when the bad guys are chasing Sarah and she is about to run into a building where a janitor is washing the floor, a camera and crew are visible in the window.
Incorrectly regarded as goofs: When Sara is in Chicago's downtown looking for her parents' building, she walks by a closed "Scotia Bank". Scotia Bank is a Canadian bank; however, it has had a branch in Chicago since 1892.
Continuity: When Dan returns the skate to Chris at the end of the movie, there is a name tag on the skate that says Sarah Anderson. In the credits she is shown as "Sara".
Continuity: In the garage, the station wagon is covered with dust and is badly in need of a clean. When they pull out, the wagon is as clean as a showroom version.
Continuity: When Chris wraps the cord around the mobster's ankle, she unplugs the cord. When he falls, the cord is plugged in.
Continuity: When Chris arrives at the Andersen's, the movie, "Halloween" is playing in the background, but the soundtrack if from a western movie. When Brenda calls, a western movie is on the television, but the Halloween soundtrack is playing.
Crew or equipment visible: When Pruitt gets out of his semi at his home, the camera crew is reflected into his rear-view mirror on his truck.
Boom mic visible: When Mr. Pruitt runs with the group out of the hospital, they are being chased by the police. They run down an alley towards the back of an ambulance. As the kids get close to the camera, you can see a shadow of a boom (dead cat) on the white wall on the right side of the frame.
Continuity: When Chris and the children start walking on the I-beam above the bad guys hideout, from the kids' point of view looking down, there is a metal chain hanging over the I-beam that they have to walk over. From the camera angle from below looking up at the kids, there is no chain.
Errors in geography: Throughout a lot of the shots of the gang in Chicago, Brad and Sarah's parent's building is shown facing them as they are running through the city. This is geographically impossible, as the diamond cut of the building actually faces Lake Michigan.