Reed will make the announcement Thursday at the Ravens training complex. He will be joined by coach John Harbaugh, general manager Ozzie Newsome and team president Dick Cass.
Reed played 12 years in the NFL, the first 11 with Baltimore. After a lackluster season with Houston and the New York Jets in 2013, he sat out last season.
The 36-year-old Reed holds the NFL record for career interception return yards and was voted The Associated Press 2004 NFL Defensive Player of the Year.
Drafted in the first round of the 2002 draft out of the University of Miami, Reed had 64 interceptions and was used occasionally as a punt returner.
He was part of Baltimore's 2012 Super Bowl champion team.
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