ABC News President Ben Sherwood made the announcement Monday in a memo to staff. Sherwood said Pitts "has a unique talent for stories about people and communities facing the longest odds."
Pitts was a CBS correspondent for 15 years, covering politics and the wars in Iraq and Afghanistan. In a 2009 memoir, Pitts revealed how he overcame a stutter and said he was essentially illiterate until about age 12. He grew up in Baltimore.
ABC News has recently seen the departures of Jake Tapper and Chris Cuomo to CNN.
The Associated Press contributed to this report.