"After discussions with Tina and her agent, it was best for both parties to go our separate ways at this time," said Mercury general manager Jim Pitman in a statement. "Due to circumstances both in and out of our control, our season has not gone according to our plan, and we will continue to pursue all avenues for improvement."
Phoenix has lost its last three games to fall to 6-12 for the season. Charles averaged 17.3 points and 7.3 rebounds per game in 16 appearances in 2022.
The 33-year-old signed a one-year deal worth $108,000 with the Mercury in February after leading the WNBA in scoring the year before while playing for the Washington Mystics.
Originally selected by the Connecticut Sun with the first overall pick in 2010, Charles has produced a Hall of Fame-caliber resume. She won the MVP award in 2012 and has earned eight All-Star nominations.