Continuity mistake: When Scott and Charlie are at Denny's, Scott picks up the eggnog placard from the table to ask the waitress about it. He then puts it back down in a different spot. However, in the shots of Charlie by himself (such as when he asks for chocolate milk), the placard is visible in the foreground, in the same place it was before Scott picked it up. (00:09:55)
Revealing mistake: When Tim Allen startles Santa Clause and he falls off of the roof, Santa's foot kicks up a blanket that was used to look like some snow on the roof. (00:14:10)
Factual error: Finishing his rounds on the morning of Christmas Day, flying over downtown Chicago, the sun is over the horizon west of Chicago, Sunrises occur in the east, not the west. (00:26:10)
Continuity mistake: When the sleigh makes the vertical take off, Santa asks Charlie if he's ready to go. We see both Bernard and Quentin look at each other and smiling as well as all the other elves behind them. In the next shot, not only are none of the elves smiling, but they also are all wearing welding goggles. (01:14:00 - 01:14:40)
Audio problem: When the elf special forces are about to take off and the female elf does a somersault, the sound that is created when they touch their wrist console can be heard over the sounds of the jet pack take off sounds. No one is even touching their wrists during the scene. (01:19:27)
Continuity mistake: During the jail break scene after the elves have used tinsel to slice off the jail door hinges, the lead elf is holding the tinsel with both hands, but when he says that tinsel is not just for decoration, he is holding it with one hand, then back to two hands when the scene cuts.
Continuity mistake: While Charlie tells Scott he knows CPR, Scott's right hand drops to his side, but when Charlie tells Scott the "SC" on his pyjamas is the same letters as his name, Scott's right hand is now resting on his right breast.
Factual error: Neal says he stopped believing in Santa Claus when he was three because he didn't get an Oscar Mayer wienie whistle. You didn't have to buy wienie whistles; the Oscar Mayer company gave them away to children for free at grocery stores. (I had one.)
Suggested correction: For a child believing in Santa, it's not the price of the gift. His parents didn't get him a weenie whistle for whatever reason, even though he asked Santa for one.
Continuity mistake: After giving Scott his business card, Neal puts his wallet in his pocket twice.
Revealing mistake: When Tim Allen is looking at the reindeer, one reindeer's ear moves. At this point you can see the metal robot in the base of the ear.
Revealing mistake: When Santa slips on Scott Calvin's snow-covered roof, you can see the "snow" wrinkle as he slides.
Other mistake: Near the beginning, Scott and Charlie are flying in the sleigh down a road next to a truck. During the entire scene, the truck driver is constantly jerking the wheel to the right and left yet the truck remains in a perfectly straight course.
Continuity mistake: Before and after Scott enters and exits the chimney pipe, the background shows the roof of the house with very little snow and the roof shingles exposed. The overhead shot showing Scott and Charlie leaving in the sleigh shows the same roof covered in snow.
Other mistake: When Santa falls off Scott Calvin's roof, he slides in a straight trajectory that lines up just off center of the front door, meaning Santa should have fallen smack down on the snowless concrete walkway, not a few feet over onto the snow-covered lawn.
Continuity mistake: In the scene where Bernard the elf appears at the Miller's house near the end of the movie, there is a shot of him walking out of the kitchen with Neal's snack that the latter had been preparing earlier (a stuffed pita shell) and he's talking to Neal as though his mouth is full from having taken a bite. However, if you look at the pita, it is still whole - not a single bite taken.
Factual error: Tim Allen drives a 1st generation Ford Taurus SHO (1989-91) in the movie, which was only available with a manual transmission. When he pulls up and parks at the Denny's, you can see his hand down on the console and the clicking sound of shifting an automatic from drive into park.
Continuity mistake: While Bernard is explaining the "Santa Clause" to Scott Calvin, an elf dressed as a pirate behind Bernard exits the scene twice.
Continuity mistake: During mother's patronising talk to Scott and Charlie (fairly at the beginning of the movie) her gloves at one stage both end up briefly in the other hand.
Continuity mistake: Right after the part where Santa fell off the roof and Scott is yelling at Charlie to stop climbing up the ladder, you will notice their roof is slanted and has a significant amount of snow on it. However, from the top of the ladder Charlie exits off with complete ease (given the circumstances of the roof and ladder position, difficult for a skilled adult let alone 6-year-old Charlie) and walks onto the roof, and the roof portion is now obviously a flat surface.
Continuity mistake: After being told that he cannot see Charlie till the next year Tim Allen steps into Charlie's house. Before he enters it's snowing, when you see him inside with Charlie in his arms you can see outside the dining room window that there is no snow, and when Charlie's mum goes outside it's snowing again.