| Mark | Athlete | School | Year | Meet |
|---|
| 49.28 | Nash Coley | Gallatin (Bozeman) (AA) | 11 | Eastern AA Divisional |
| 49.55 | Jeff Lillard | Glacier (AA) | 12 | Western AA Divisional |
| 49.57 | Jackson Tarver | Great Falls CMR (AA) | 11 | Eastern AA Divisional |
| 49.92 | Wilson Schmidt | Belgrade (AA) | 9 | Eastern AA Divisional |
| 50.13 | Garrett Dahlke | Gallatin (Bozeman) (AA) | 12 | Skor DeKam Invite |
| 50.15 | Anthony Ramirez | Billings West (AA) | 10 | Eastern AA Divisional |
| 50.34 | Brady Kolendich | Missoula Sentinel (AA) | 11 | Western AA Divisional |
| 50.39 | Henry Ballinger | Helena (AA) | 12 | State AA Championship |
| 50.50 | Peyton Nelson | Helena Capital (AA) | 11 | Helena Crosstown Meet |
| 50.79 | Osker Patterson | Gallatin (Bozeman) (AA) | 11 | Skor DeKam Invite |
| 50.97 | Ryan Harrington | Great Falls (AA) | 11 | Great Falls Crosstown Dual |
| 51.01 | Keagen Crosby | Missoula Sentinel (AA) | 12 | Glacier-Sentinel Dual |
| 51.14 | Aaron French | Helena (AA) | 11 | Skor DeKam Invite |
| 51.16 | William Hollensteiner | Flathead (AA) | 9 | State AA Championship |
| 51.17 | Merek Mihelish | Helena Capital (AA) | 10 | Helena Small Schools Meet |
| 51.19 | Aiden Marceau | Missoula Big Sky (AA) | 11 | State AA Championship |
| 51.19 | Titus Sykes | Bozeman (AA) | 11 | State AA Championship |
| 51.20 | Luke Ruch | Helena (AA) | 10 | Western AA Divisional |
| 51.23 | Ben Shaules | Missoula Sentinel (AA) | 10 | Western AA Divisional |
| 51.39 | Emmanuel White | Helena Capital (AA) | 11 | State AA Championship |
| 51.48 | Tevin Wetzel | Helena (AA) | 10 | Skor DeKam Invite |
| 51.51 | Ian Harrison | Missoula Sentinel (AA) | 12 | Western AA Divisional |
| 51.57 | Issac Kohler | Butte (AA) | 12 | Bozeman Triangular |
| 51.67 | Ethan Anderson | Glacier (AA) | 10 | Columbia Falls-Glacier Dual |
| 51.85 | Travis Ryland-Davis | Helena (AA) | 10 | Western AA Divisional |
| 51.93 | Colby Worthington | Billings West (AA) | 12 | Eastern AA Divisional |
| 51.94 | Cohen Kastelitz | Glacier (AA) | 11 | Western AA Divisional |
| 51.97 | Shae Warner | Glacier (AA) | 10 | Western AA Divisional |
| 51.99 | Zachary Stidham | Billings Skyview (AA) | 11 | Eastern AA Divisional |