Sean Bean, Sophie Turner, Maisie Williams, Kit Harington. It's hard now, ten years after the premiere of Game of Thrones on HBO to imagine the Stark family outside of the superstar actors who portrayed them on screen.
However, the massive novels (five so far) written by George R.R. Martin existed long before the casting directors began picking faces for television. So, how closely do favorite actors stick to the descriptions provided by Martin in the books?
Eddard Stark
Ned Stark, unlikely patriarch of the Stark clan (after the death of his elder brother) always had the long brown hair Sean Bean sports in season one of Game of Thrones. He also had a long face and a closely trimmed beard that was beginning to gray (to match his gray eyes). He was also shorter than his elder brother.
While Sean Bean seems like a close match, it should also be mentioned that, in the books, Ned Stark was only supposed to be about thirty-five years old. See a younger version above by El-Andyjack.
Catelyn Stark
Catelyn, like her husband, was much younger in the novels than she is on screen. Michelle Fairley matches Catelyn's fair skin tone and auburn hair, but she was not in her thirties when Game of Thrones came out on television.
Catelyn is also supposed to have blue eyes and high cheekbones, along with long fingers. If it weren't for the age difference, Fairley would be an excellent, almost perfect, choice for the character. This illustration of a younger Catelyn Tully is by ynorka.
Robb Stark
The eldest of the six Stark children (this includes Jon) Robb was supposed to have a stocky build (while Richard Madden is relatively tall). He is supposed to take after his mother with thick red/brown hair and blue eyes.
Madden certainly gets the hair right. But, like the actors cast to portray his parents, Madden is much older than the Robb Stark of the George R.R. Martin novels. On the page Robb, when readers meet him, is supposed to be no more than fourteen. Antonio Jos Manzanedo draws a younger book version of the OG King in the North.
Jon Snow
Snow, Stark, Targaryen, when it comes down to it Jon is a member of the Stark family and his looks prove that. He is supposed to look more like the Stark side of the family than any of his brothers.
Jon is described as quick and lean. He has the same long face as Ned and dark hair and gray eyes (almost black). Kit Harington covers most of this description though, again like the rest of the actors, he was aged up from the novel where, like Robb, he is supposed to be fourteen. See Teilku's art for comparison.
Sansa Stark
Sansa Stark, eldest daughter of Ned and Catelyn Stark, takes after her mother and her brother rob. She is beautiful, with the high cheekbones, blue eyes, and auburn hair of the Tully side of her family.
On-screen Sophie Turner comes pretty close, though she did dye her hair for the part. Her eyes are green rather than blue, but still. Again, she was aged up slightly in season one, where Sansa is supposed to be eleven. See a blue-eyed Sansa by Kodabomb above.
Arya Stark
Arya is the only legitimate child of Ned and Catelyn who is described as having the Stark coloring on the pages of Game of Thrones. Like her father, she has a long face, gray eyes, and brown hair. She is skinny, athletic, and rather plain. In the books, some call her "Arya Horseface". Even before cutting her hair, she is often mistaken for a boy.
Maisie Williams certainly fits the bill when she was cast, at the tender age of twelve. In the books, however, Arya, in season one, is only supposed to be nine. See a young faceless Arya by yinmiushi above.
Bran Stark
With Bran Stark, the casting directors seem to have finally gone off book. Again, like siblings Robb and Sansa, Bran is supposed to have the coloring of the Tully side of his family. He is said to have thick auburn hair and blue eyes. (See Alkanet's version above.)
Obviously on-screen Isaac Hempstead-Wright looks a lot more like sister Arya (Maisie Williams) and father Ned (Sean Bean). Bran is supposed to be seven in season one of the HBO series, though Hempstead-Wright was ten.
Rickon Stark
The youngest and least explored Stark sibling, Rickon, again takes after his mother's side of the family on the page. He is said to have auburn hair and bright blue eyes. He's supposed to smile easily. He's also supposed to be four years old. (See a red headed baby Rickon with his siblings by MiiBT above.)
Obviously Art Parkinson was not four years old when HBO began filming Game of Thrones in 2011. His hair too was much closer to Sean Bean's than Michelle Fairley's.
Benjen Stark
Benjen, youngest sibling of Ned Stark, uncle to the brood of six siblings, and Ranger for the Night's Watch, was played by Joseph Mawle. He is supposed to have sharp features and blue/gray eyes. He is thin with long legs.
Mawle seems to fit the bill pretty well, even if he gets the least screen time of any of the Stark family in the eight seasons of the HBO series. See YvyB13's version above.