| Lane | Team | Squad | Athlete 1 | Athlete 2 | Athlete 3 | Athlete 4 | Seed |
|---|---|---|---|---|---|---|---|
| 3 | Parkway South High School | A | Lawson | Schaefferkoetter | Lyons | Watkins | NT |
| 4 | Lafayette (Wildwood) High School | B | 1:44.55 | ||||
| 5 | Seckman High School | A | Reelitz | Dawson | Dibbert | Bruenger | 1:50.00 |
| 6 | Ladue Horton Watkins High School | A | NT |
| Lane | Team | Squad | Athlete 1 | Athlete 2 | Athlete 3 | Athlete 4 | Seed |
|---|---|---|---|---|---|---|---|
| 1 | Webster Groves High School | C | Reed | Sutton | Bennett | Wall | 1:44.34 |
| 2 | Christian Brothers College High | C | Gillespie | Cobb | Porter | Wagner | 1:43.00 |
| 3 | Mehlville High School | C | Evans | Becerra | McClure | Sanders | 1:41.27 |
| 4 | Liberty (Wentzville) High School | A | Lawrence | Lively | Cosey | Struttmann | 1:40.95 |
| 5 | Kirkwood High School | B | Araneta | Griffin | Loper | Barry | 1:41.00 |
| 6 | Lafayette (Wildwood) High School | C | 1:41.55 | ||||
| 7 | Liberty (Wentzville) High School | B | Orf | Minnix | Mills | Ross | DQ |
| Lane | Team | Squad | Athlete 1 | Athlete 2 | Athlete 3 | Athlete 4 | Seed |
|---|---|---|---|---|---|---|---|
| 1 | Webster Groves High School | B | Skiles | Brewer | Smith | Weir | 1:40.38 |
| 2 | Mehlville High School | A | Guittar | Moehlenbrock | Traore | Shelton | 1:40.03 |
| 3 | Kirkwood High School | A | McKee | Steuby | Boswinkel | Cauble | 1:38.67 |
| 4 | Christian Brothers College High | B | Hayden | Hendrix | Cothrine | Pauley | 1:38.30 |
| 5 | Webster Groves High School | A | Robinson | Salmon | Abotsi | Robinson | 1:38.38 |
| 6 | Kirkwood High School | C | Webb | Burns | Washington | Lindsay | 1:38.67 |
| 7 | Mehlville High School | B | Watson | Jones | Hannam-Lewis | Storch | 1:40.27 |
| 8 | Eureka High School | A | Davis | MCELROY | KOHL | Robinson | 1:40.53 |
| Lane | Team | Squad | Athlete 1 | Athlete 2 | Athlete 3 | Athlete 4 | Seed |
|---|---|---|---|---|---|---|---|
| 1 | Liberty (Wentzville) High School | C | Lamm | Vanhoy | Adams | Burton Wadibia | 1:37.95 |
| 2 | Christian Brothers College High | A | Busby | Washington | McClellan | Jackson | 1:37.10 |
| 3 | Parkway North High School | B | Harrold | Lindsey | White | Vinson | 1:36.00 |
| 4 | Rolla High School | A | Harris | Hamer | Wassilak | Gibson | 1:33.70 |
| 5 | Lafayette (Wildwood) High School | A | TINSLEY | VEHIGE | Retych | TUGGLES | 1:35.55 |
| 6 | Parkway North High School | A | Griffin | Conley | Dunlap | Rhodes | 1:37.00 |
| 7 | DeSmet Jesuit High School | A | Byerley | Houston | Robinson | McCaster | 1:37.55 |
| 8 | St. Louis University High School | A | Pace | Kreuter | Baur | Chaffee | 1:38.20 |