The 35-year-old Portuguese made $105 million before tax in 2019, placing his value over the $1 billion mark.
Ronaldo was named as the fourth-biggest earning celebrity in 2020, trailing tennis star, Roger Federer, rapper Kanye West, and Kylie Jenner.
Argentine and Barcelona player, Lionel Messi was rated fifth and earned $104m in the year under review, according to the magazine.
The former Manchester United man, aside from Tiger Woods and ex-boxer, Floyd Mayweather, is the third athlete ever to accumulate such wealth and the first person to do so in a team sport.
Ronaldo is said to have made $650m in wages in his professional career so far with the rest of his money gotten from endorsements.
With a total of 429.3 million followers across all social media platforms, as well as his $65 million annual salary and bonus at current club Juventus, Ronaldo remains one of the best paid athletes in sport.
Also, the footballer has a fashion and lifestyle brand, hotel chain as well as a museum in his Funchal hometown in Madeira.
The attacker’s earnings were hit by the COVID-19 pandemic when Juventus players accepted a 30 percent pay cut to their salaries.
Even though Messi’s salary reduced due to the pandemic, Forbes is expecting the Argentine to join the billionaire’s club in 2021.