| Mark | Athlete | School | Year | Meet |
|---|
| 38.24 | Colin Dolese | Missoula Hellgate (AA) | 11 | State AA |
| 38.52 | Chris Lange | Missoula Big Sky (AA) | 11 | State AA |
| 39.22 | Josh Barrows | Helena (AA) | 10 | State AA |
| 39.22 | Jay Owens | Missoula Big Sky (AA) | 12 | State AA |
| 39.99 | Mason Storm | Great Falls CMR (AA) | 12 | Great Falls Crosstown Meet |
| 40.02 | Brian Sinrud | Helena Capital (AA) | 12 | State AA |
| 40.18 | Adam Cebulla | Glacier (AA) | 12 | Glacier-Coulmbia Falls Dual |
| 40.24 | Taylor Trollope | Billings Skyview (AA) | 10 | State AA |
| 40.63 | Kyle Romero | Billings Skyview (AA) | 12 | State AA |
| 40.89 | Riley Barta | Billings Skyview (AA) | 10 | State AA |
| 41.03 | Michael Kossman | Billings West (AA) | 12 | State AA |
| 41.08 | Nate Williams | Great Falls (AA) | 10 | Great Falls Crosstown Meet |
| 41.38 | Kaedon Caprara | Butte (AA) | 12 | Skor-DeKam Invitational |
| 41.39 | Chance Edwards | Great Falls (AA) | 12 | Great Falls-Capital Dual |
| 41.53 | Tom Donahue | Billings West (AA) | 11 | Billings City Meet |
| 41.67 | Shane Mitchell | Helena Capital (AA) | 12 | Helena Crosstown Meet |
| 41.80 | Jake Egley | Flathead (AA) | 12 | Archie Roe Invitational |