Joan Thomas grew up on the Canadian prairies. She studied English at the University of Winnipeg and taught English in three different high schools, as well as in a teacher-training program in the Caribbean. She has worked as a freelance writer, reviewer, and editor, and as Writing and Publishing Consultant for the Manitoba Arts Council.

Thomas has been a frequent book reviewer for the <i>Globe and Mail</i> since 1993 and for two years wrote a biweekly feature review in the <i>Globe</i>. In 2010, she, along with Pasha Malla and Alissa York, selected the stories for the <i>Journey Prize Anthology</i> (McClelland & Stewart) and in 1999 she was co-editor (with Heidi Harms) of <i>Turn of the Story: Canadian Short Fiction on the Eve of the Millennium</i> (House of Anansi Press). Her interview-based features with writers have been published in the <i>Winnipeg Free Press</i> and <i>Prairie Fire</i>.

Thomas has been writing fiction since about 2000. Her 2008 novel <i>Reading by Lightning</i> won the Commonwealth Prize for Best First Book (Canada and the Caribbean) and the Amazon.ca First Novel Award. Her second novel, <i>Curiosity</i>, was published in April 2010 by McClelland & Stewart. It was named a Quill and Quire Book of the Year and was nominated for the ScotiaBank Giller Prize and the International IMPAC-Dublin Literary Award.