On February 8, 2017, the Cubs traded Dewees to the Kansas City Royals for pitcher Alec Mills.

[11] Dewees spent the 2017 season with the Northwest Arkansas Naturals of the Double-A Texas League[12] where he posted a .272 batting average with nine home runs, 52 RBIs, and 20 stolen bases in 126 games.

[13] In 2018, Dewees played for the Omaha Storm Chasers of the Triple-A Pacific Coast League (PCL).

He began the 2022 season with Triple-A Iowa, playing in 13 games and hitting .286/.333/.429 with one home run, 6 RBI, and 4 stolen bases.

He was later shut down and underwent surgery on the same knee to repair a cartilage issue, causing his to miss the remainder of the year.