Since 1939, the Pioneer Baseball League has operated in the Mountain States region as an MLB affiliated league. Beginning in 2021, the PBL will be an MLB Partner League with teams in Montana (Billings, Missoula and Great Falls), Idaho (Boise and Idaho Falls), Utah (Ogden) and Colorado (Grand Junction and Colorado Springs). The Northern Colorado Owlz, formerly the Orem Owlz, join the League for the 2022 season.
Over the course of the season, each team will play 76 games in a split schedule. In the playoffs, first-half division winners will play second-half division winners in a one game playoff. The division playoff winners will meet for a final best-of-three series.
The Pioneer Baseball League is intended to serve as a developmental league, with no player on the Active List having more than three years of prior professional baseball service. Each team is limited to a roster of 25 active players.