Book publisher Macmillan Children's Books plan to publish a new Gruffalo picture book in September 2026, marking the first addition to the series in over two decades, book news company The Bookseller revealed on Wednesday.

Julia Donaldson and Axel Scheffler, the UK's top-selling author-illustrator duo, are collaborating on the untitled third instalment following the global success of The Gruffalo (1999) and The Gruffalo's Child (2004).

World rights were acquired from RCW and Axel Scheffler directly, and the release will be supported by a major marketing campaign. The publisher is positioning the book as one of the biggest launches in its history, aimed at revitalising global interest in reading through partnerships with charitable organisations.

Leading the initiative is the National Literacy Trust, which will use the launch to support its Early Words Matter campaign. The programme aims to tackle declining reading enjoyment among children, with recent findings showing only one in three children in the UK read for pleasure in their free time.

With more than 5.3 million copies sold across the first two Gruffalo titles and translations in 113 languages and dialects, the series remains one of the most successful in global children's publishing. Donaldson cited the NLT's work as the inspiration to revisit an old idea for the story, while Scheffler expressed surprise and delight at the opportunity to return to the Gruffalo's world.

Macmillan is inviting global publishing partners to align with local literacy charities to expand the campaign's impact.