| Lane | Team | Squad | Athlete 1 | Athlete 2 | Athlete 3 | Athlete 4 | Seed | Note |
|---|---|---|---|---|---|---|---|---|
| 1 | Clark County High School | A | MCKAY | Lovell | NEVES | Veloso | NT | Unverified: |
| 2 | South Shelby High School | B | Nelson | Buckman | Avery | Hendricks | 1:00.00 | Unverified: |
| 3 | Southern Boone County High Schoo | A | Johnson | Hinton | Patton | Patton | 57.71 | Verified |
| 4 | Monroe City High School | B | Clark | Flick | Miller | Reinberg | 57.11 | Verified |
| 5 | Monroe City High School | A | Foss | Lehenbauer | Martin | Hays | 57.11 | Verified |
| 6 | Hannibal High School | B | Vohs | Johnson | Greenwell | Evans | 58.00 | Unverified: |
| 7 | Marion County High School | A | Bock | Hathaway | Lee | Myers | 1:00.63 | Verified |
| Lane | Team | Squad | Athlete 1 | Athlete 2 | Athlete 3 | Athlete 4 | Seed | Note |
|---|---|---|---|---|---|---|---|---|
| 1 | Highland High School | A | Sharpe | Keith | Bringer | Reed | 54.80 | Verified |
| 2 | South Shelby High School | A | McWilliams | Mitchell | Roush | Roush | 54.34 | Verified |
| 3 | Macon High School | A | Terry | McVicker | Anderson | Brown | 53.59 | Verified |
| 4 | Centralia High School | A | Adams | Hawkins | Fox | Walters | 52.34 | Verified |
| 5 | Palmyra High School | A | Redd | Voss | McBride | White | 53.25 | Verified |
| 6 | Hannibal High School | A | Stewart | LaJoy | Dean | Hark | 53.75 | Verified |
| 7 | Louisiana High School | A | Campbell | Ries | Chatman | McGlothin | 54.46 | Verified |
| 8 | Mark Twain High School | A | Boleach | Hudelson | Hawn | Ross | 56.64 | Verified |