Private schools, in some form, existed long before the concept of free public education in America. Students were often educated through church-sponsored programs, private tutoring, and boarding schools. Public schools on a large scale were proposed by Horace Mann in the 1830s. The concept gained momentum, and by 1870, nearly 80% of kids aged 5 to 14 were enrolled in public schools. Today, according to the most recent enrollment data, about 4.7 million students—or 10% of students enrolled in kindergarten through grade 12—are enrolled in private schools.

Private schools are widely marketed as a better option when compared to public schools, and private school proponents will often point to standardized test scores to substantiate this claim. While private school students have consistently outperformed public school students on standardized tests, recent studies have shown private schools themselves are not the primary driver of success, nor are standardized tests the most accurate measure of student well-being.

Researchers have found that student success is more directly related to family attributes, like having parents who graduated from college, and higher incomes—more common amongst private school students than public school students—than simply whether the students attended a public or private school.

Still, private schools provide unique advantages and opportunities like smaller class sizes, more individualized instruction, and greater curricular flexibility. To better understand how private school offerings vary across the country, Stacker compiled a list of the best private high schools in Illinois using 2023 rankings from Niche. Niche uses eight weighted factors for its rankings. A majority of the score is based on academics and grades, but other factors include culture and diversity, health and safety, clubs and activities, resources, and surveys of parents, teachers and students.

#30. St. Viator High School

– Enrollment: 875 (16:1 student to teacher ratio)
– Grades served: 9-12
– City: Arlington Heights
– Niche grade: A+

#29. Regina Dominican High School

– Enrollment: 258 (9:1 student to teacher ratio)
– Grades served: 9-12
– City: Wilmette
– Niche grade: A+

#28. GCE Lab School

– Enrollment: 61 (6:1 student to teacher ratio)
– Grades served: 9-12
– City: Chicago
– Niche grade: A+

#27. Ida Crown Jewish Academy

– Enrollment: 220 (6:1 student to teacher ratio)
– Grades served: 9-12
– City: Skokie
– Niche grade: A+

#26. Naperville Christian Academy

– Enrollment: 128 (7:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Naperville
– Niche grade: A+

#25. Wolcott College Prep

– Enrollment: 150 (4:1 student to teacher ratio)
– Grades served: 9-12
– City: Chicago
– Niche grade: A+

#24. St. Francis High School

– Enrollment: 698 (13:1 student to teacher ratio)
– Grades served: 9-12
– City: Wheaton
– Niche grade: A+

#23. Benet Academy

– Enrollment: 1,357 (20:1 student to teacher ratio)
– Grades served: 9-12
– City: Lisle
– Niche grade: A+

#22. GEMS World Academy Chicago

– Enrollment: 440 (5:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Chicago
– Niche grade: A+

#21. Keith Country Day School

– Enrollment: 286 (8:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Rockford
– Niche grade: A+

#20. Fenwick High School

– Enrollment: 1,197 (14:1 student to teacher ratio)
– Grades served: 9-12
– City: Oak Park
– Niche grade: A+

#19. Loyola Academy

– Enrollment: 2,000 (13:1 student to teacher ratio)
– Grades served: 9-12
– City: Wilmette
– Niche grade: A+

#18. The Einstein Academy

– Enrollment: 89 (5:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Elgin
– Niche grade: A+

#17. The Chicago Academy for the Arts

– Enrollment: 119 (2:1 student to teacher ratio)
– Grades served: 9-12
– City: Chicago
– Niche grade: A+

#16. Christian Heritage Academy

– Enrollment: 421 (11:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Northfield
– Niche grade: A+

#15. Morgan Park Academy

– Enrollment: 490 (9:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Chicago
– Niche grade: A+

#14. Elgin Academy

– Enrollment: 227 (5:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Elgin
– Niche grade: A+

#13. Northridge Preparatory School

– Enrollment: 330 (10:1 student to teacher ratio)
– Grades served: 6-12
– City: Niles
– Niche grade: A+

#12. Beacon Academy

– Enrollment: 213 (7:1 student to teacher ratio)
– Grades served: 9-12
– City: Evanston
– Niche grade: A+

#11. St. Ignatius College Prep

– Enrollment: 1,512 (16:1 student to teacher ratio)
– Grades served: 9-12
– City: Chicago
– Niche grade: A+

#10. Rochelle Zell Jewish High School

– Enrollment: 185 (6:1 student to teacher ratio)
– Grades served: 9-12
– City: Deerfield
– Niche grade: A+

#9. Lycée Français de Chicago

– Enrollment: 746 (7:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Chicago
– Niche grade: A+

#8. Woodlands Academy of the Sacred Heart

– Enrollment: 131 (6:1 student to teacher ratio)
– Grades served: 9-12
– City: Lake Forest
– Niche grade: A+

#7. Francis W. Parker School

– Enrollment: 935 (9:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Chicago
– Niche grade: A+

#6. Roycemore School

– Enrollment: 244 (6:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Evanston
– Niche grade: A+

#5. British International School of Chicago, South Loop

– Enrollment: 651 (9:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Chicago
– Niche grade: A+

#4. North Shore Country Day

– Enrollment: 547 (7:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Winnetka
– Niche grade: A+

#3. Latin School of Chicago

– Enrollment: 1,155 (8:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Chicago
– Niche grade: A+

#2. Lake Forest Academy

– Enrollment: 436 (6:1 student to teacher ratio)
– Grades served: 9-12
– City: Lake Forest
– Niche grade: A+

#1. University of Chicago Laboratory Schools

– Enrollment: 2,051 (8:1 student to teacher ratio)
– Grades served: PK, K-12
– City: Chicago
– Niche grade: A+