The average private high school in Illinois has 236 students (2025).
The largest private high school in Illinois is American School with 6,319 students.
School Size Range: 645
6,319
Avg. School Size: 1,120
Largest Illinois Private High Schools (2025)
School
# Students
Grades
Location
Rank: #11.
American School![American School Photo American School Photo]()

Alternative School
Students: 6,319
Grades: 6-12
2200 E 170th St
Lansing, IL 60438
(708) 418-2800
Lansing, IL 60438
(708) 418-2800
Rank: #22.
Students: 2,224
Grades: PK-12
1362 E 59th Street
Chicago, IL 60637
(773) 702-9450
Chicago, IL 60637
(773) 702-9450
Rank: #33.
Students: 2,072
Grades: 9-12
1100 Laramie Ave
Wilmette, IL 60091
(847) 256-1100
Wilmette, IL 60091
(847) 256-1100
Rank: #44.
Marist High School![Marist High School Photo Marist High School Photo]()

(Catholic)
Students: 1,780
Grades: 9-12
4200 W 115th St
Chicago, IL 60655
(773) 881-5300
Chicago, IL 60655
(773) 881-5300
Rank: #55.
St. Ignatius College Prep
(Catholic)
Students: 1,373
Grades: 9-12
1076 West Roosevelt Road
Chicago, IL 60608
(312) 421-5900
Chicago, IL 60608
(312) 421-5900
Rank: #66.
Students: 1,269
Grades: PK-12
188 W Butterfield Rd
Elmhurst, IL 60126
(630) 833-4616
Elmhurst, IL 60126
(630) 833-4616
Rank: #77.
Benet Academy
(Catholic)
Students: 1,265
Grades: 9-12
2200 Maple Ave
Lisle, IL 60532
(630) 719-2782
Lisle, IL 60532
(630) 719-2782
Rank: #88.
Students: 1,172
Grades: PK-12
59 W North Blvd
Chicago, IL 60610
(312) 582-6014
Chicago, IL 60610
(312) 582-6014
Rank: #99.
Students: 1,107
Grades: 9-12
1 Carmel Pkwy
Mundelein, IL 60060
(847) 566-3000
Mundelein, IL 60060
(847) 566-3000
Rank: #1010.
Fenwick High School
(Catholic)
Students: 1,101
Grades: 9-12
505 Washington Blvd
Oak Park, IL 60302
(708) 948-0332
Oak Park, IL 60302
(708) 948-0332
Rank: #1111.
Students: 1,015
Grades: 9-12
5900 W Belmont Avenue
Chicago, IL 60634
(773) 282-8844
Chicago, IL 60634
(773) 282-8844
Rank: #1212.
Students: 942
Grades: 9-12
3633 N California Ave
Chicago, IL 60618
(773) 539-3600
Chicago, IL 60618
(773) 539-3600
Rank: #1313.
St. Laurence High School
(Catholic)
Students: 913
Grades: 9-12
5556 W 77th St
Burbank, IL 60459
(708) 458-6900
Burbank, IL 60459
(708) 458-6900
Rank: #1414.
Students: 907
Grades: PK-12
330 W Webster Ave
Chicago, IL 60614
(773) 797-5501
Chicago, IL 60614
(773) 797-5501
Rank: #1515.
Students: 889
Grades: PK-12
200 N Roselle Road
Schaumburg, IL 60194
(847) 885-3230
Schaumburg, IL 60194
(847) 885-3230
Rank: #1616.
Mother Mcauley Liberal Arts High School![Mother Mcauley Liberal Arts High School Photo Mother Mcauley Liberal Arts High School Photo]()

All-girls (Catholic)
Students: 832
Grades: 9-12
3737 W 99th Street
Chicago, IL 60655
(773) 881-6507
Chicago, IL 60655
(773) 881-6507
Rank: #1717.
Students: 819
Grades: 9-12
700 Ashland Ave
Chicago Heights, IL 60411
(708) 755-7565
Chicago Heights, IL 60411
(708) 755-7565
Rank: #1818.
St. Blase Polish Catholic School
Special Program Emphasis (Catholic)
Students: 817
Grades: PK-12
6101 S 75th Ave
Summit Argo, IL 60501
(708) 458-8772
Summit Argo, IL 60501
(708) 458-8772
Rank: #1919.
St. Viator High School
(Catholic)
Students: 808
Grades: 9-12
1213 E Oakton St
Arlington Heights, IL 60004
(847) 392-4050
Arlington Heights, IL 60004
(847) 392-4050
Rank: #2020.
Students: 803
Grades: PK-12
1401 N Bell School Road
Rockford, IL 61107
(815) 391-8006
Rockford, IL 61107
(815) 391-8006
Rank: #2121.
Students: 798
Grades: PK-12
5950 Spring Creek Rd
Rockford, IL 61114
(815) 877-2600
Rockford, IL 61114
(815) 877-2600
Rank: #2222.
Students: 777
Grades: PK-12
1929 W. Wilson Avenue
Chicago, IL 60640
(773) 665-0066
Chicago, IL 60640
(773) 665-0066
Rank: #2323.
Students: 748
Grades: PK-12
3411 N Alpine Rd
Rockford, IL 61114
(815) 877-9551
Rockford, IL 61114
(815) 877-9551
Rank: #2424.
Bishop Mcnamara Catholic High School
(Catholic)
Students: 743
Grades: PK-12
550 W Brookmont Blvd
Kankakee, IL 60901
(815) 932-7413
Kankakee, IL 60901
(815) 932-7413
Rank: #2525.
Students: 734
Grades: 9-12
7655 W Dempster Street
Niles, IL 60714
(847) 965-2900
Niles, IL 60714
(847) 965-2900
Rank: #2626.
Mcc Academy-elementary
(Islamic)
Students: 721
Grades: PK-12
9301 Gross Point Rd
Skokie, IL 60076
(224) 534-7638
Skokie, IL 60076
(224) 534-7638
Rank: #2727.
Nazareth Academy
(Catholic)
Students: 720
Grades: 9-12
1209 West Ogden Avenue
La Grange Park, IL 60526
(708) 354-0061
La Grange Park, IL 60526
(708) 354-0061
Rank: #28 - 2928. - 29.
Students: 717
Grades: NS-12
161 West 9th Street
Chicago, IL 60605
(773) 998-2472
Chicago, IL 60605
(773) 998-2472
Rank: #28 - 2928. - 29.
Universal School![Universal School Photo Universal School Photo]()

(Islamic)
Students: 717
Grades: PK-12
7350 W 93rd St
Bridgeview, IL 60455
(708) 599-4100
Bridgeview, IL 60455
(708) 599-4100
Rank: #3030.
Students: 703
Grades: 9-12
5105 N Sheridan Road
Peoria, IL 61614
(309) 691-8741
Peoria, IL 61614
(309) 691-8741
Rank: #3131.
De La Salle Institute - Institute Campus![De La Salle Institute - Institute Campus Photo - De La Salle Institute De La Salle Institute - Institute Campus Photo - De La Salle Institute]()

(Catholic)
Students: 699
Grades: 9-12
3434 S Michigan Ave
Chicago, IL 60616
(312) 842-7355
Chicago, IL 60616
(312) 842-7355
Rank: #3232.
St. Francis High School
(Catholic)
Students: 697
Grades: 9-12
2130 W Roosevelt Rd
Wheaton, IL 60187
(630) 668-5800
Wheaton, IL 60187
(630) 668-5800
Rank: #3333.
Brother Rice High School - Chicago![Brother Rice High School - Chicago Photo Brother Rice High School - Chicago Photo]()

All-boys (Catholic)
Students: 671
Grades: 9-12
10001 S Pulaski Rd
Chicago, IL 60655
(773) 429-4300
Chicago, IL 60655
(773) 429-4300
Rank: #3434.
Wheaton Academy![Wheaton Academy Photo Wheaton Academy Photo]()

(Christian)
Students: 667
Grades: 9-12
900 Prince Crossing Rd
West Chicago, IL 60185
(630) 562-7500
West Chicago, IL 60185
(630) 562-7500
Rank: #3535.
Students: 645
Grades: NS-12
2255 Sullivan Road
Aurora, IL 60506
(630) 892-1551
Aurora, IL 60506
(630) 892-1551
Show 100 more private schools in IL (out of 382 total schools)
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Frequently Asked Questions
What is the Illinois average private high schools student size?
The Illinois average private high schools student size is 236 for 2025.
What are the private high schools with the largest student size in Illinois?
The top ranked private high schools in Illinois include American School, University of Chicago Laboratory Schools and Loyola Academy.
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