Snape's family background is mostly shown in flashbacks during the course of the last three novels. Snape was born to Eileen Prince, a witch, and Tobias Snape, a Muggle, making him a half-blood (hence the name, "Half-Blood Prince"). This is rare for a Death Eater, as remarked in the last book, though Voldemort himself also had a Muggle father. Snape spent his early childhood living with his parents in a small house in Spinner's End. Snape's family was a poor one and he is described as wearing ill-fitting clothes "that were so mismatched that it looked deliberate". As a child, Snape was apparently neglected and his parents often fought with one another. Snape was very eager to leave his home to go to Hogwarts.

Spinner's End is a Muggle street, on which sits Severus Snape's house. It is described as one of several streets of identical brick houses. The street is located near a dirty river, the bank of which is strewn with litter. A mill with a tall chimney is close by. From the description of its surroundings, it is likely that this is the house Severus Snape grew up in, thus making the place the fictitious town of Cokeworth.

Snape's front door opens directly into a sitting room that has the feeling of a dark, padded cell, containing walls filled with books, threadbare furniture, and a dim, candle-filled lamp that hangs from the ceiling. A hidden door leads to a narrow staircase. Spinner's End first appears in Half-Blood Prince, when Snape is visited by Bellatrix Lestrange and Narcissa Malfoy. In Deathly Hallows, it is revealed that Snape lived at Spinner's End as a young child and that Lily Potter and Petunia Dursley lived in the same town.