Continuity mistake: After Pongo spots Anita and Perdita walking towards the park, Pongo moves the time forward on the clock and he leaves the dial's hinged bezel open as he rushes to the door and barks, but when Roger checks the time on the clock the bezel is closed. (00:06:20)
Other mistake: The puppies apparently can't see when Lucky puts his head in front of the TV. The first time we see him do this, he is barely covering anything, but the puppies claim they can't see.
Continuity mistake: During a fight scene, Patch starts approaching Jasper. In the next shot it is a different puppy. The shot after that shows that it was Lucky (the back markings a giveaway) and not Patch.
Continuity mistake: When Nanny discovers the puppies are stolen the calendar in the house shows December. However, the newspaper showing the headline of them being stolen is dated the 2nd November.
Other mistake: When they are counting the puppies at the end they count the puppies on the stairs. One of the puppies has a red collar, only the original 15 have collars, so this dog is counted twice. So the title of the movie should be 100 dalmatians.
Character mistake: When Nanny says, "Look, here's Lucky!" the puppy she picks up does not have a collar on, therefore that cannot be Lucky, as Lucky is one of the original 15 with collars. (01:16:48)
