Onatolu earned a bachelor's degree in communications at the University of Nebraska-Omaha, and aspires to have a career in broadcasting.
He has an identical twin brother named Taiwo, who was his teammate at Nebraska-Omaha and now is a graduate assistant on the Mavericks’ staff.
Onatolu was born in Chicago, but spent 3 years as a child in his parents' home country of Nigeria.
After going undrafted in 2007, Onatolu attended an Edmonton Eskimos minicamp after his twin brother Taiwo had a similar experience.
After playing in just four games in the 2012 season, Onatolu was released by the Panthers on April 16, 2013.