One of the best deep threats over the last decade in the league, Smith announced his retirement on social media Friday.
"Dear football, I knew this day would come, and to be completely honest, I've been preparing for it my entire career," Smith said. "You and I both knew the game for me wouldn't last forever. It's the NFL circle of life and I'm prepared for what's next."
The Ravens selected Smith in the second round of the 2011 NFL Draft out of Maryland. He enjoyed his best seasons in Baltimore, winning a Super Bowl title in 2012 and recording 65 catches for 1,128 yards and four touchdowns in 2013.
Smith tallied a career-high 11 touchdown catches in 2014, the season before he left the Ravens in free agency.
"I was just a young kid with big dreams," Smith said. "I didn't know at any time that you would help pave the way for me to accomplish all of my goals."
Smith signed with the 49ers in 2015 and spent two seasons in San Francisco. He later went on to play for the Carolina Panthers and Philadelphia Eagles, winning his second Super Bowl with the Eagles in 2017.
The 30-year-old wideout's decision comes 12 days after the Panthers released him.