Which award did J.K. Rowling win for Harry Potter and the Prisoner of Azkaban in 1999?

J.K. Rowling won the 1999 Whitbread Children’s Book Award for Harry Potter and the Prisoner of Azkaban.

The third Harry Potter novel was published in 1999 and continued the series’ rapid rise in popularity. Its plot introduced Sirius Black, Remus Lupin, and the history surrounding Harry’s parents, while expanding the magical world beyond Hogwarts’ usual school-year mysteries.

The Whitbread Book Awards, later known as the Costa Book Awards, recognised books across several categories. Prisoner of Azkaban won the children’s category in 1999, adding to Rowling’s growing list of literary prizes.

This award should not be confused with the Carnegie Medal or the Guardian Children’s Fiction Prize, both major British children’s-literature honours but not the prize asked about here.