But the German media and marketing magazine 'WundV' claims that the Spaniard also commands the most income from external sponsors.
The report said that, in the past year, the 30-year-old made between EUR 7 and 8 million just from his personal backers, including Puma, Tag-Heuer and Santander.
In second place is Michael Schumacher, the seven time world champion.
Despite winning only a single podium in the two and a half seasons since returning to F1 in 2010, 43-year-old Schumacher made between 5 and 6 million in personal sponsorship in the past year, said the report.
The current world champion, Sebastian Vettel, reportedly makes only 3-4 million in estimated personal sponsorship; about the same as Jenson Button, but less than McLaren's Lewis Hamilton (5m).