| Mark | Athlete | School | Year | Meet |
|---|
| 48.10 | William Hollensteiner | Flathead (AA) | 11 | Archie Roe Invitational |
| 49.18 | Lane Chivers | Flathead (AA) | 12 | Western AA Divisional |
| 49.44 | Wilson Schmidt | Belgrade (AA) | 11 | Skyview/Bozeman/Belgrade Tri |
| 49.71 | Ethan DeLeon | Billings Senior (AA) | 11 | Eastern AA Divisional |
| 49.94 | Adam Guajardo | Missoula Big Sky (AA) | 11 | Western AA Divisional |
| 49.96 | Reid Bartholomew | Gallatin (Bozeman) (AA) | 11 | Eastern AA Divisional |
| 50.09 | Luke Ruch | Helena (AA) | 12 | Skor Dekam Invite |
| 50.11 | Michael Hughes | Billings Skyview (AA) | 12 | Eastern AA Divisional |
| 50.18 | Cooper Nelson | Helena Capital (AA) | 11 | Skor Dekam Invite |
| 50.27 | Caleb Conver | Billings West (AA) | 12 | Senior/Gallatin/West Triangular |
| 50.31 | Ben Bliven | Flathead (AA) | 12 | Western AA Divisional |
| 50.43 | Chandler Christensen | Billings Skyview (AA) | 12 | Eastern AA Divisional |
| 50.56 | Dylan Hill | Helena (AA) | 11 | Helena Crosstown Meet |
| 50.71 | Travis Ryland-Davis | Helena (AA) | 12 | Western AA Divisional |
| 50.81 | Blake Williams | Missoula Big Sky (AA) | 11 | Missoula "Greg Rice" City Meet |
| 50.81 | Lucas Kadillak | Bozeman (AA) | 12 | Last Chance Qualifier |
| 50.97 | Louis Kamps | Gallatin (Bozeman) (AA) | 11 | Bozeman Crosstown Dual |
| 51.02 | Grady Caton | Missoula Hellgate (AA) | 12 | Hellgate/Sentinel/Flathead Tri |
| 51.05 | Thatcher Schmidt | Belgrade (AA) | 11 | Eastern AA Divisional |
| 51.16 | Gage Wardell | Billings Skyview (AA) | 11 | Eastern AA Divisional |
| 51.18 | Ethan Young | Great Falls CMR (AA) | 11 | Eastern AA Divisional |
| 51.21 | Christian Landers | Bozeman (AA) | 11 | Eastern AA Divisional |
| 51.24 | Teigan Blomquist | Billings West (AA) | 11 | Eastern AA Divisional |
| 51.28 | Kellen Gibson | Missoula Sentinel (AA) | 11 | Western AA Divisional |
| 51.30 | Kasen Kastner | Flathead (AA) | 12 | Hellgate/Sentinel/Flathead Tri |
| 51.43 | Boone Davis | Helena Capital (AA) | 10 | Capital vs CMR Dual |
| 51.48 | Ethan Anderson | Glacier (AA) | 12 | Glacier/Sentinel Dual |
| 51.56 | Shae Warner | Glacier (AA) | 12 | Columbia Falls/Glacier Dual |
| 51.59 | Drew Almquist | Helena Capital (AA) | 10 | East Helena Quad Meet |
| 51.62 | Ryland Humphrey | Billings West (AA) | 11 | Senior/Gallatin/West Triangular |
| 51.65 | Axel Kowalski | Helena (AA) | 9 | Western AA Divisional |
| 51.76 | Owen Thiel | Glacier (AA) | 11 | Columbia Falls/Glacier Dual |
| 51.85 | Santiago Soto | Billings Skyview (AA) | 9 | Eastern AA Divisional |
| 51.92 | Calvin Paczkowski | Billings West (AA) | 11 | Senior/Gallatin/West Triangular |
| 51.92 | Dylan Almquist | Helena Capital (AA) | 12 | Skor Dekam Invite |
| 51.93 | Cormack Batt | Missoula Big Sky (AA) | 11 | Big Sky Quad |
| 51.95 | Simon Lillard | Glacier (AA) | 12 | CMR/Glacier Dual |
| 52.00 | Jace Vogel | Billings West (AA) | 9 | Eastern AA Divisional |