Bowles had reportedly received interest from the Chicago Bears for the same role. He was fired as Jets head coach in late December.
He'll once again work under head coach Bruce Arians in Tampa Bay. Bowles was Arians' defensive coordinator with the Arizona Cardinals from 2013-14 before being hired by the Jets.
Arizona's defense ranked seventh and fifth in points allowed per game in 2013 and 2014, respectively.
Only the Oakland Raiders allowed more than the Buccaneers' 29.0 points per game in 2018.