| Mark | Athlete | School | Year | Meet |
|---|
| 45.35 | Havyn Vandenacre | Broadwater/Townsend (B) | 10 | Russ Plicher Top 10 |
| 45.43 | Alyssa Boshart | Sweet Grass Co./Big Timber (B) | 12 | State B |
| 45.69 | Gracie Bradley | Colstrip (B) | 12 | Midland Roundtable Top 10 |
| 47.14 | Teigan Taylor | Fairview (B) | 12 | Norm Girard North/East Top 10 |
| 47.72 | Isabelle Berry | Loyola Sacred Heart (B) | 10 | State B |
| 47.86 | Brayli Reimer | Red Lodge (B) | 11 | State B |
| 48.53 | Jasmyn Murphy | Three Forks (B) | 12 | Southern B Divisional |
| 48.87 | Rebecca Middleton | Huntley Project (B) | 11 | State B |
| 48.91 | Shaylee Quenzer | Red Lodge (B) | 10 | State B |