#1 Largest Private Schools in St. Louis County, MO
Greenways Academy
Alternative school · Grades 1–12
3,015 students
Saint Louis, MO
BOverall grade3,015 students
2026 lists
Largest Private Schools in St. Louis County, MO
The private schools in St. Louis County, MO with the most students. Top 50 of 138 schools.
#2 Largest Private Schools in St. Louis County, MO
Micds
Independent school · Grades Pre-K–12
1,220 students
Saint Louis, MO
A+Overall grade1,220 students9 students per teacher
#3 Largest Private Schools in St. Louis County, MO
St. Louis University High School
Independent Catholic school · Grades 9–12
1,036 students
Saint Louis, MO
AOverall gradeAll boys1,036 students12 students per teacher
#4 Largest Private Schools in St. Louis County, MO
Westminster Christian Academy
Presbyterian school · Grades 7–12
940 students
Town and Country, MO
AOverall grade940 students11 students per teacher
#5 Largest Private Schools in St. Louis County, MO
Chaminade College Preparatory School
Independent Catholic school · Grades 6–12
872 students
Saint Louis, MO
B+Overall gradeAll boys872 students10 students per teacher
#6 Largest Private Schools in St. Louis County, MO
St. Joseph's Academy
Independent Catholic school · Grades 9–12
587 students
Saint Louis, MO
BOverall gradeAll girls587 students12 students per teacher
#7 Largest Private Schools in St. Louis County, MO
St. John Vianney High School
Independent Catholic school · Grades 9–12
581 students
Kirkwood, MO
A-Overall gradeAll boys581 students12 students per teacher
#8 Largest Private Schools in St. Louis County, MO
Visitation Academy
Independent Catholic school · Grades Pre-K–12
555 students
Saint Louis, MO
AOverall gradeAll girls555 students9 students per teacher
#9 Largest Private Schools in St. Louis County, MO
Lutheran High School South
Lutheran (Missouri Synod) school · Grades 9–12
550 students
Saint Louis, MO
BOverall grade550 students13 students per teacher
#10 Largest Private Schools in St. Louis County, MO
Cor Jesu Academy
Independent Catholic school · Grades 9–12
519 students
Saint Louis, MO
A+Overall gradeAll girls519 students11 students per teacher
#11 Largest Private Schools in St. Louis County, MO
St. Catherine Laboure School
Parish school · Grades K–8
482 students
Saint Louis, MO
BOverall grade482 students18 students per teacher
#12 Largest Private Schools in St. Louis County, MO
St. Gabriel the Archangel School
Parish school · Grades K–8
475 students
Saint Louis, MO
BOverall grade475 students15 students per teacher
#13 Largest Private Schools in St. Louis County, MO
Villa Duchesne Upper and Lower School
Independent Catholic school · Grades Pre-K–12
465 students
Saint Louis, MO
BOverall grade465 students9 students per teacher
#14 Largest Private Schools in St. Louis County, MO
Villa Duchesne School
Independent Catholic school · Grades Pre-K–12
459 students
Saint Louis, MO
A+Overall grade459 students4 students per teacher
#15 Largest Private Schools in St. Louis County, MO
St. Gerard Majella Catholic School
Parish school · Grades Pre-K–8
457 students
Kirkwood, MO
BOverall grade457 students14 students per teacher
#16 Largest Private Schools in St. Louis County, MO
Cardinal Ritter College Prep High School
Diocesan school · Grades 9–12
453 students
Saint Louis, MO
BOverall grade453 students13 students per teacher
#17 Largest Private Schools in St. Louis County, MO
Incarnate Word Parish School
Parish school · Grades K–8
448 students
Chesterfield, MO
B-Overall grade448 students18 students per teacher
#18 Largest Private Schools in St. Louis County, MO
Christ Community Lutheran School
Lutheran (Missouri Synod) school · Grades Pre-K–8
447 students
Kirkwood, MO
B-Overall grade447 students17 students per teacher
#19 Largest Private Schools in St. Louis County, MO
Principia School
Religious school · Grades Pre-K–12
423 students
Saint Louis, MO
A+Overall grade423 students8 students per teacher
#20 Largest Private Schools in St. Louis County, MO
Holy Infant Elementary School
Parish school · Grades Pre-K–8
420 students
Ballwin, MO
B-Overall grade420 students16 students per teacher
#21 Largest Private Schools in St. Louis County, MO
Ascension School
Parish school · Grades K–8
412 students
Chesterfield, MO
BOverall grade412 students15 students per teacher
#22 Largest Private Schools in St. Louis County, MO
Whitfield School
Independent school · Grades 6–12
407 students
Saint Louis, MO
A+Overall grade407 students9 students per teacher
#23 Largest Private Schools in St. Louis County, MO
Holy Cross Academy
Parish school · Grades Pre-K–8
402 students
Saint Louis, MO
BOverall grade402 students13 students per teacher
#24 Largest Private Schools in St. Louis County, MO
St. Margaret Mary Alacoque School
Parish school · Grades Pre-K–8
397 students
Saint Louis, MO
B-Overall grade397 students17 students per teacher
From official public records, updated October 2026.