| Mark | School | Meet |
|---|
| 48.81 | Havre (A) | Nelson-Thomas ABC Meet |
| 49.10 | Corvallis (A) | Nelson-Thomas ABC Meet |
| 49.57 | Whitefish (A) | Whitefish ARM Invitational |
| 50.31 | Hamilton (A) | Nelson-Thomas ABC Meet |
| 50.31 | Frenchtown (A) | Nelson-Thomas ABC Meet |
| 50.78 | Custer Co./Miles City (A) | Eastern A Divisional |
| 50.99 | Beaverhead Co./Dillon (A) | Western A Divisional |
| 51.39 | Fergus/Lewistown (A) | Midland Roundtable Top 10 |
| 51.42 | Laurel (A) | Eastern A Divisional |
| 51.67 | Sidney (A) | Eastern A Divisional |
| 51.67 | Lockwood (A) | Sidney Twilight Meet |
| 51.88 | Billings Central (A) | Billings Invite |
| 52.12 | Columbia Falls (A) | Columbia Falls/Whitefish Dual |
| 52.27 | Polson (A) | Western A Divisional |
| 52.34 | Dawson Co./Glendive (A) | Eastern A Divisional |
| 52.53 | Bigfork (A) | Nelson-Thomas ABC Meet |
| 52.62 | Stevensville (A) | Western A Divisional |