The have declined their $25 million club option on left-handed starting pitcher and will pay him a $10 million buyout instead, per Bruce Levine of WSCR-AM and 670 The Score.
Lester inked a six-year, $155 million contract with the team before the 2015 season. He went 77-44 with a 3.64 ERA and 940 strikeouts in 1,002.2 innings during his six seasons in Chicago.
The 36-year-old was named a National League All-Star in 2016 and 2018 and led the league with 18 wins in 2018.
The 2016 season, which ended with the Cubs' first World Series title since 1908, was arguably Lester's best in Chicago.