And J K herself is said to be earning more from merchandise than sales of her books and Harry Potter toys are set to be a huge Christmas draw.
Money keeps coming
Philip Beresford puts together the Sunday Times list of the country's wealthiest people.
He said: "If this carries on over the seven books she is writing and all the films, she could be on course to be the world's first billionaire author."
Rowling has now sold 124 million books around the world and the success doesn't look like it's about to slow down just yet.