JK has earned a whopping £125 million in 2003 thanks to the release of Order Of The Phoenix and profits from The Chamber Of Secrets film.
She came fifth in the list of Britain's 500 highest earners and was one of only two women to make the top 10.
First place went to Chelsea owner Roman Abramovich, who netted £564 million.
The youngest person to make the list was 14-year-old Harry Potter actor Daniel Radcliffe.
He earned £1.75 million - enough to put him in joint 489th place.
Money-spinning
It's been a money-spinning year for David Beckham, too.
His move to Real Madrid helped him climb 11 places to 34th in the list, with earnings of £20.5million.
He remains the UK's highest paid footballer.
The list also revealed that the Queen of Pop and the Queen of England are taking home similar earnings.
With £15 million, London-based Madonna was the country's eighth highest-earning woman.
The Queen came seventh with £15.6 million.
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