In the booth, the censor removes a sprig of mistletoe from the bulletin board next to Brice Cummings's head. The mistletoe was not there in an earlier shot.
When Claire hits Frank with the door, she has a roll of wrapping paper in her shopping bag. When she drops her bag to see if he's all right, the paper's gone. When he picks her bag up, the roll is back in the bag.
At the end, on set there are scenes with snow on people. During cut scenes, the snow comes and goes.
After Frank Cross stumbles onto the stage after breaking out of the sewer, he wrestles with an actor from the fake movie set. He grabs the actor's walking stick, and in between shots the stick moves from his right hand to his left.
When Cross gets locked in the back of the cab, he tries to open each door, but the handles come off in his hands. Between taking them off and holding them up by his face, the heavy end of each handle switches to the opposite end.
When the phone auto dials Claires number, the shot shows the last 4 numbers pressed as being 4992. But when Frank picks up phone, the phone number for Claire ends with 7733.
After Frank Cross wakes up in his office after Lew visits him, he drinks some vodka that has a golf ball in it. When he drops the golf ball on his desk, it bounces three times in front of Frank's face. On the second and third bounces, the ball actually goes higher than on its first bounce. Although this is "impossible," it is meant to emphasize the supernatural origins of the ball. Also note that the sound effects correspond with this "supernatural" activity.
During the broadcast of A Christmas Carol, Scrooge tosses a coin to a boy so he can buy a Christmas goose. The shot seen in the control room monitor shows the coin falling in slow motion. This was more than likely a pre-recorded shot used for dramatic emphasis within the broadcast, which is common practice during live telecasts.
When Eliot Loudermilk confronts Frank, he fires three shots from the double-barreled shotgun before reloading.
When Frank falls down the stairs at his brother's house and the Ghost of Christmas Present floats down after him, her levitation wires can be seen briefly before being hidden behind her wings.
When Frank Cross's office door is being beaten down by Lew Hayward, it is obviously made of metal, as it retains the dents from the impacts on the outside. However, when the door finally shatters, it is clearly made of wood.
The Ghost and Frank walk into the office Christmas party in 1968. Despite being invisible to the guests, a woman in a brown dress looks right at them as they move toward her.
When Frank enters the sewers, it can be seen that some of the pieces of ice hanging down are nothing more than pieces of cloth. They can be seen to blow in the wind as Frank moves around the sewer area.
In 1969, Frank gives Claire a set of Ginsu knives as a gift. Ginsu knives were first sold in 1978 under a different name, and the "Ginsu" name was coined in 1983.
When Frank Cross is facing the dog at his brother's apartment in the hallway, the dog handler's shadow can be seen waving the dog off.
The telephone which auto-dials moves around a bit, so it can be seen that someone pulls strings from under the telephone.
When Grace is taking Calvin home, she exits the 45th Rd-Courthouse Sq station in Queens. But when the Ghost of Christmas Present takes Frank to see Grace and her family, she says she's taking him to Harlem, which is in Manhattan.
When Frank calls Claire, he says they broke up 15 years before. However, in the flashback to when they broke up, it's 1971, 17 years before the film's present.
After the encounter with the Ghost of Christmas Past, Frank decides to visit Claire at work. The business card she had given him says "Operation Reach Out," but the doors Frank walks into say "Operation Outreach."