Southwestern Conference (Illinois) Current Membership Current Membership

| School | Location_ | Mascot | Colors | Enrollment | IHSA_Classes_2_3_4 | IHSA_Music_Class | IHSA_Football_Class | IHSA_Cheerleading_Class |
|---|---|---|---|---|---|---|---|---|
| Alton High School | Alton, IL | Redbirds | Red, Gray | 2135 | AA/3A/4A | AA | 7A | Large squad |
| Belleville East High School | Belleville, IL | Lancers | Columbia Blue, Navy Blue | 2600 | AA/3A/4A | AA | 8A | Large squad |
| Belleville West High School | Belleville, IL | Maroons | Maroon, White | 2434 | AA/3A/4A | AA | 7A | Large squad |
| Collinsville High School | Collinsville, IL | Kahoks | Purple, White | 2020 | AA/3A/4A | AA | 7A | Large squad |
| East St. Louis Senior High School | East St. Louis, IL | Flyers/ Flyerettes | Orange, Blue | 2146 | AA/3A/4A | AA | 7A | Large squad |
| Edwardsville High School | Edwardsville, IL | Tigers | Orange, Black | 2514 | AA/3A/4A | AA | 8A | Large squad |
| Granite City High School | Granite City, IL | Warriors | Red, Black, White | 2129 | AA/3A/4A | AA | 7A | Large squad |