On July 8, 2018, the Giants traded Bahr, Austin Jackson, and Cory Gearrin to the Texas Rangers in exchange for a PTBNL or cash considerations.[6][7] He finished the year with the Down East Wood Ducks of the High–ACarolina League. In 24 starts between Augusta, San Jose and the Ducks, he went 10–8 with a 3.52 ERA.[8] Bahr was assigned back to Down East to open the 2019 season,[9][10] and went 6–1 with a 1.71 ERA in 58 innings for them. On June 21, he was promoted to the Frisco RoughRiders of the Double-ATexas League,[11] and went 4–3 with a 3.23 ERA in 64 innings for them.[12][13] Bahr was named the Texas Rangers 2019 Nolan Ryan Minor League Pitcher of the Year.[14]
Bahr did not play in a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.[15] Bahr spent the 2021 season with the Round Rock Express of the Triple-A West, struggling to a 2–1 record with a 9.00 ERA over 33 innings.[16] Bahr returned to Round Rock to open the 2022 season.[17] After posting a 5.90 ERA with 46 strikeouts over 20 appearances, Bahr was released by the Rangers organization on July 25.
