Up on the Wooftop (2015) on Netflix

Plot summary

Toby is a dog smaller than most, and he dreams of leading Santa's sleigh. He climbs aboard during a test flight, and when the sleigh leaves he is stranded in suburban Iowa. The Anderson family finds him there, and Toby sets out to convince them of who he really is so that they will help him return to the North Pole before Christmas Eve. The household has troubles of its own: the children are dealing with growing pains, their father has lost sight of what the holiday means, and a scheming mall Santa and the elves who assist him have plans of their own.