| SQ | IESA - 7th Boys | 52.54 |
| Lane | Team | Squad | Athlete 1 | Athlete 2 | Athlete 3 | Athlete 4 | Seed | Note |
|---|---|---|---|---|---|---|---|---|
| 2 | Winston | A | Egbe | Ramirez | Tyser | Munoz | 1:02.40 | |
| 3 | Jack London | A | Bush | Cioclov | Basilio | Hazard | 59.70 | |
| 4 | South (Arlington Heights) | A | McGrath | Olson | Hernandez | English | 59.82 |
| Lane | Team | Squad | Athlete 1 | Athlete 2 | Athlete 3 | Athlete 4 | Seed | Note |
|---|---|---|---|---|---|---|---|---|
| 2 | Aptakisic | A | Kumar | Cernansky | Clark | Boehm | 58.54 | |
| 3 | Lincoln (Mt. Prospect) | A | Koziol | Robinson | Martinez | Behles | 57.10 | |
| 4 | Twin Groves | A | Chon | Worth | Grzeda | Subramanian | 57.92 | |
| 5 | Holmes | A | Alarcon | Alcantar | Mendoza | Palmer | 59.00 |
| Lane | Team | Squad | Athlete 1 | Athlete 2 | Athlete 3 | Athlete 4 | Seed | Note |
|---|---|---|---|---|---|---|---|---|
| 1 | Wilmette | A | Marini | Covell | Lahey | Cho | 56.84 | |
| 2 | Haven | A | Frisch | Schmeckpeper | Long | Godbolt | 56.25 | |
| 3 | MacArthur | A | Bryant | Aquino | Travis | Berk | 51.80 | |
| 4 | Chute | A | Wilson-Thomas | Scott | Byhre | Amos-Frazier | 54.75 | |
| 5 | Daniel Wright | A | F. | K. | S. | H. | 56.74 | |
| 6 | Thomas | A | Hollins | Vates | Sharma | Kilchytskyi | 57.00 |