Federer, who is a 20-time grand slam champion, boasts the best endorsement portfolio in the world of sport, with $100 million (£80.7m) of his earnings coming off the court.
He leapfrogs football stars Cristiano Ronaldo and Lionel Messi to secure top spot. The Juventus and Barcelona superstars, made £84.8m and £84m respectively.
Forbes explained that the Coronavirus pandemic triggered salary cuts for Messi and Ronaldo, paving the way for Federer.
“The coronavirus pandemic triggered salary cuts for soccer stars Messi and Ronaldo, clearing the way for a tennis player to rank as the world’s highest-paid athlete for the first time,” said Forbes’ Senior Editor Kurt Badenhausen.
“Roger Federer is the perfect pitchman for companies, resulting in an unparalleled endorsement portfolio of blue-chip brands worth $100 million a year for the tennis great.”