The 45-year-old Czech legend, a five-time NHL scoring champion and 13-time All-Star right wing, was waived through the league after scoring one goal and setting up six more for the Flames this season.
Jagr, who has the second-most points and second-most games played in NHL history, has not played since the end of December due to what the Flames called a lower body injury.
"Although I am very disappointed that things did not turn out as we had hoped due to a number of circumstances, I am deeply grateful to the Flames, the fans and the City of Calgary for having welcomed me so generously," Jagr said. "I now look forward to continuing the season in Kladno."
That's the team Jagr played for as a junior and began his professional career with in 1988. He jumped to the NHL in 1990 and won his only Stanley Cup titles in 1991 and 1992 with the Pittsburgh Penguins, for whom he played over 11 seasons.
He returned to the NHL and played for Philadelphia, Dallas, Boston, New Jersey and Florida before joining Calgary this season. He was within reach of Gordie Howe's all-time record of games played before being injured.