What is J.K. Rowling's first adult novel?

J.K. Rowling’s first adult novel is The Casual Vacancy. Published on 27 September 2012, it was Rowling’s first novel outside the Harry Potter series and her first book written specifically for adult readers.

The story takes place in Pagford, a fictional West Country town. When parish councillor Barry Fairbrother dies suddenly, his vacant council seat triggers a bitter local election. The novel explores class divisions, poverty, addiction, family conflict and political hypocrisy rather than magic or fantasy.

The title refers to a real British local-government term: a “casual vacancy” is an unexpected opening in an elected position between regular elections. Rowling found the phrase in a local-government reference book after initially working under the title Responsible.

A common mix-up is The Cuckoo’s Calling, which appeared in 2013 under the pseudonym Robert Galbraith. It was Rowling’s first crime novel, but The Casual Vacancy came first as her adult fiction debut.