On November 20, 2020, Bannon was added to the 40-man roster.[11] Bannon spent the majority of the 2021 season in Triple-A Norfolk, but struggled to a .177/.297/.370 batting line with 15 home runs, 36 RBI, and 9 stolen bases.
On May 12, 2022, Bannon was recalled from Norfolk and promoted to the major leagues for the first time.[12] Bannon made his MLB debut the same day against the St. Louis Cardinals, and recorded his first hit in his first at-bat off of Steven Matz.[13] It was one of two hits he had for the Orioles, in 14 at-bats over four games.[14]
Atlanta Braves
On August 8, 2022, Bannon was claimed off waivers by the Dodgers,[15] However they designated for assignment just four days later without him appearing in any games in the Dodgers system.[16]
On August 16, 2022, Bannon was claimed off waivers by the Atlanta Braves.[17] He was designated for assignment on November 11.[18]
Houston Astros
On November 18, 2022, Bannon was claimed off waivers by the Chicago Cubs. However on December 2, he was claimed off waivers again, this time by the Houston Astros.[19] Bannon was optioned to the Triple-A Sugar Land Space Cowboys to begin the 2023 season.[20] On April 18, 2023, Bannon was recalled by the Astros after OF Chas McCormick was placed the 10-day injured list.[21] In 2 games with the Astros, Bannon went 0-6 with 3 strikeouts.[22] On May 8, Bannon was optioned to Triple-A Sugar Land after McCormick was activated from the injured list.[23] In 81 games for Sugar Land, he batted .230 with 15 home runs and 43 RBI. On September 3, Bannon was designated for assignment following the waiver claim of Bennett Sousa.[24] He cleared waivers and was sent outright to Triple–A Sugar Land on September 5.[25] Bannon elected free agency following the season on November 6.[26]
New York Mets
On December 11, 2023, Bannon signed a minor league contract with the New York Mets.[27]