Business Loop I-90 - Missoula

This business route begins at Exit 101 and turns south alongside U.S. 93 (Reserve Street) to a folded diamond interchange with Broadway Street (old U.S. 10). U.S. 93 remains south on Reserve Street to U.S. 12, while Business Loop I-90 turns southeast along Broadway Street to the Missoula city center and the University of Montana via U.S. 12 (Madison Street Bridge) west. A five block section of the route doubles as Business U.S. 12 between Higgins Avenue and Madison Street. U.S. 12 joins Business Loop I-90 east from there to Van Buren Street, where the two turn north to meet Interstate 90 at Exit 105.

The route is well signed as of 2016, with an array of traveler services and lodging lining the Reserve Street leg.