#1 Fastest-Growing Private Schools in King County, WA
Cedar Crest Academy Bellewood
Independent school · Grades Pre-K–5
Enrollment up 352% in about a decade
Bellevue, WA
B-Overall grade190 students13 students per teacher
2026 lists
Fastest-Growing Private Schools in King County, WA
Private schools in King County, WA whose enrollment has grown the most over the past decade. Top 44 of 44 schools.
#2 Fastest-Growing Private Schools in King County, WA
Overcomer Academy
Christian school (nondenominational) · Grades Pre-K–8
Enrollment up 341% in about a decade
Auburn, WA
B-Overall grade194 students16 students per teacher
#3 Fastest-Growing Private Schools in King County, WA
Bellevue Montessori School
Montessori school · Grades 1–6
Enrollment up 332% in about a decade
Bellevue, WA
BOverall grade255 students15 students per teacher
#4 Fastest-Growing Private Schools in King County, WA
Yellow Wood Academy
Alternative school · Grades 4–12
Enrollment up 166% in about a decade
Mercer Island, WA
AOverall grade101 students2 students per teacher
#5 Fastest-Growing Private Schools in King County, WA
Hamlin Robinson School
Special education school · Grades 1–8
Enrollment up 158% in about a decade
Seattle, WA
B+Overall grade389 students7 students per teacher
#6 Fastest-Growing Private Schools in King County, WA
Eastside Preparatory School
Independent school · Grades 5–12
Enrollment up 123% in about a decade
Kirkland, WA
A+Overall grade536 students9 students per teacher
#7 Fastest-Growing Private Schools in King County, WA
Providence Classical Christian School
Calvinist school · Grades Pre-K–12
Enrollment up 116% in about a decade
Bothell, WA
A-Overall grade350 students13 students per teacher
#8 Fastest-Growing Private Schools in King County, WA
Perkins School
Independent school · Grades K–5
Enrollment up 111% in about a decade
Seattle, WA
A+Overall grade129 students8 students per teacher
#9 Fastest-Growing Private Schools in King County, WA
Kapka Cooperative School
Independent school · Grades K–5
Enrollment up 83% in about a decade
Seattle, WA
AOverall grade66 students8 students per teacher
#10 Fastest-Growing Private Schools in King County, WA
Seattle Academy
Independent school · Grades 6–12
Enrollment up 80% in about a decade
Seattle, WA
A+Overall grade1,170 students8 students per teacher
#11 Fastest-Growing Private Schools in King County, WA
Medina Academy
Islamic school · Grades Pre-K–8
Enrollment up 78% in about a decade
Bellevue, WA
A+Overall grade229 students11 students per teacher
#12 Fastest-Growing Private Schools in King County, WA
Sunbeams Lutheran School
Lutheran (Missouri Synod) school · Grades Pre-K–5
Enrollment up 74% in about a decade
Kent, WA
AOverall grade54 students13 students per teacher
#13 Fastest-Growing Private Schools in King County, WA
Heritage Christian Academy
Baptist school · Grades Pre-K–10
Enrollment up 73% in about a decade
Bothell, WA
A+Overall grade253 students8 students per teacher
#14 Fastest-Growing Private Schools in King County, WA
Glendale Lutheran School
Lutheran (ELCA) school · Grades Pre-K–8
Enrollment up 70% in about a decade
Burien, WA
AOverall grade63 students11 students per teacher
#15 Fastest-Growing Private Schools in King County, WA
Harbor School
Independent school · Grades K–8
Enrollment up 67% in about a decade
Vashon, WA
B+Overall grade77 students8 students per teacher
#16 Fastest-Growing Private Schools in King County, WA
St. Therese Catholic Academy
Diocesan school · Grades K–8
Enrollment up 60% in about a decade
Seattle, WA
A+Overall grade198 students8 students per teacher
#17 Fastest-Growing Private Schools in King County, WA
Renton Christian School
Assembly of God school · Grades Pre-K–8
Enrollment up 58% in about a decade
Renton, WA
B+Overall grade690 students16 students per teacher
#18 Fastest-Growing Private Schools in King County, WA
Three Tree Montessori School
Montessori school · Grades Pre-K–6
Enrollment up 55% in about a decade
Burien, WA
A-Overall grade73 students10 students per teacher
#19 Fastest-Growing Private Schools in King County, WA
Westside School
Independent school · Grades Pre-K–8
Enrollment up 53% in about a decade
Seattle, WA
BOverall grade340 students12 students per teacher
#20 Fastest-Growing Private Schools in King County, WA
Woodinville Montessori School
Montessori school · Grades Pre-K–12
Enrollment up 52% in about a decade
Bothell, WA
A+Overall grade312 students7 students per teacher
#21 Fastest-Growing Private Schools in King County, WA
Menachem Mendel Seattle Cheder Day School
Jewish day school · Grades Pre-K–8
Enrollment up 52% in about a decade
Seattle, WA
A-Overall grade88 students6 students per teacher
#22 Fastest-Growing Private Schools in King County, WA
Cascade Vista Baptist School
Baptist school · Grades Pre-K–12
Enrollment up 40% in about a decade
Kent, WA
B+Overall grade123 students11 students per teacher
#23 Fastest-Growing Private Schools in King County, WA
Cascadia School
Independent school · Grades Pre-K–5
Enrollment up 37% in about a decade
Redmond, WA
BOverall grade97 students10 students per teacher
#24 Fastest-Growing Private Schools in King County, WA
Bellevue Children's Academy
Independent school · Grades Pre-K–4
Enrollment up 33% in about a decade
Bellevue, WA
B+Overall grade541 students8 students per teacher
From official public records, updated October 2026.