Mark Spitz – $20 Million

Mark Spitz started competing in swimming events at an early age and held 18 records just when he was 10. Named one of the most outstanding athletes, he set records in every competition he participated in, even during his high school years. Mark is one of the most decorated Olympian sports personalities of all time.

At the age of 15, Mark dominated the swimming world, and his talent underwater not only helped him gain global recognition but has also skyrocketed his fortune. The sportsman retired from his professional career just in his early twenties, and he could certainly do that given his multi-million dollar net worth.