"Over the last five years, C.J. developed from an undrafted player into an important member of our team," Broncos president of football operations/general manager John Elway said. "We appreciate all he did as a Bronco, especially during our Super Bowl season, and thank him for his many contributions on and off the field."
Anderson, who had his first career 1,000-yard season in 2017, was the team's leading rusher last season and has been with the Broncos since he made the roster as an undrafted rookie in 2013.
The Broncos had matched a four-year, $18 million offer sheet from the Miami Dolphins in 2016 to keep Anderson, 27, and that deal had two years remaining on it. The move comes as the Broncos opened their offseason program Monday.
Anderson's release or a trade have been possibilities since the end of the season, something Anderson himself acknowledged several times along the way. Broncos coach Vance Joseph outlined a much bigger role for Booker at the league meetings last month.
Anderson's contract also gave the Broncos the ability to move on without any penalty of "dead money" -- salary-cap charges for players no longer on the roster. At $4.5 million, Anderson would have had the fourth-highest base salary at the position for the coming season. But the structure of the deal meant if Anderson was released, the Broncos would not be charged any dead money.
There is also the matter of the draft class for the Broncos, who currently have the No. 5 overall selection with all eight of their picks coming in the first five rounds.
If quarterbacks are among the first three or four players taken, the Broncos could have the chance to select from a group of players that would include Penn State running back Saquon Barkley. Many teams consider Barkley and North Carolina State defensive end Bradley Chubb the best players in the draft.
But there is plenty of running back talent beyond Barkley. Georgia's combo of Sony Michel and Nick Chubb, along with LSU's Derrius Guice, USC's Ronald Jones II, San Diego State's Rashaad Penny and Auburn's Kerryon Johnson all have No. 1 back potential and could be selected before the second round is over.
Penny is one of the players the Broncos have hosted at their complex for a pre-draft visit.
Elway has routinely said he subscribes to the idea of taking the highest-graded player on the Broncos' draft board at the time each of their picks come around, no matter what the team needs.