When Santa Claus (Richard Riehle) travels to New York City and gets hit by a cab, loses his memory and gets the crystal that keeps him eternal stolen, it is up to his new friend, his puppy, Puppy Paws (Zachary Gordon), to save him. Meanwhile, a young orphan named Quinn (Kaitlyn Maher) arrives at a foster home run by a strict and no-nonsense woman named Ms. Stout (Wendi McLendon-Covey) who forbids anything that children love: toys, Christmas decorations, singing, even pets. She has a furnace that burns all the toys she confiscates from the girls. Despite the harsh rules she has to follow while staying at the foster home, Quinn eventually befriends the girls, including Janie (G. Hannelius) and Willamina (Madison Pettis). In order to save Christmas, Eli (Danny Woodburn) and Eddy (Richard Kind) the uncanny elf dog have to go to New York City to save Santa and Paws. But when Santa (Bud) is in the hospital, it takes the help of Quinn and Willamina to save Santa. When Kate and James take Bud from the hospital, Paws tells Eli to put his crystal next to Santa, he wakes up to find that Paws is a stuffed animal. They rush back to the North Pole and Paws turns into a full-grown dog named Santa Paws (Mitchel Musso), and Christmas is back on. Ms. Stout is fired from her job of taking care of the orphan girls at the foster home, much to the excitement of the girls, and Willamina and Quinn are both adopted to James and Kate Hucklebuckle. Also at the foster home, Mrs. Gibson and the orphans welcome Augustus because he brought a lot of money for them.
- Kaitlyn Maher as Quinn, the young orphan. She finds Paws in the alley behind the foster home.
- Madison Pettis as Willamina (Will for short), the oldest girl out of all the orphans. She does not believe in Christmas until she accidentally gets stuck in the basement with Paws.
- Richard Riehle as Santa Claus
- Danny Woodburn as Eli, Santa's head elf.
- Wendi McLendon-Covey as Ms. Stout, the strict no-nonsense headmistress of the girls home who finds Christmas, toys and anything that children love annoying or offensive. She is eventually fired as a result of the abusive treatment she has inflicted upon the girls.
- G. Hannelius as Janie, an orphan who is best friends with Willamina.
- Michelle Creber as Taylor, an orphan.
- Melody B Choi as Mary, an orphan.
- Nicole Leduc as Meg, an orphan.
- John Ducey as James Hucklebuckle, husband of Kate Hucklebuckle.
- Bonnie Somerville as Kate Hucklebuckle, wife of James Hucklebuckle.
- Chris Coppola as Augustus (Gus for short), a poor homeless man.
- Jonathan Morgan Heit as Jimmy, a boy scout who helps search for Santa.
- Patrika Darbo as Mrs. Claus
- Pete Gardner as Franklin, Ms. Stout's boyfriend as well as a dogcatcher.
- Bill Cobbs as Mr. Stewart
- Zachary Gordon as Puppy Paws and Mitchel Musso as Santa Paws, the Great Pyrenees of whom only people that believe in Christmas can understand what he is saying. He is a stuffed animal when the crystal on his neck is removed.
- Richard Kind as Eddy, a happy-go-lucky elf dog Jack Russell Terrier who is also Eli's assistant.
- Jason Connery as Haggis, a Scottish Terrier who's "always ready to take action".
- Christopher Massey as Rasta, a reggae Puli who is "laidback" and "easygoing".
- Josh Flitter as T-Money, a streetwise hip-hop Bulldog who is "super cool".
- Diedrich Bader as Comet, one of Santa's reindeer.
- Michael Deyermond as Dancer, one of Santa's reindeer.