| Academy of Our Lady of Mercy
| Milford | CT | 9th-12th | none | Girls only | 440 | Roman Catholic |
| Avon Old Farms School
| Avon | CT | 9th-12th | 9th-12th | Boys only | 405 | None |
| Canterbury School 4/5 based on 1 student review(s) | New Milford | CT | 9th-PG | 9th-PG | Coed | 380 | Roman Catholic |
| Chase Collegiate School
| Waterbury | CT | PK-12th | none | Coed | 451 | None |
| Cheshire Academy 3.2/5 based on 1 student review(s) | Cheshire | CT | 6th-PG | 9th-PG | Coed | 378 | None |
| Choate Rosemary Hall 4.6/5 based on 10 student review(s) | Wallingford | CT | 9th-PG | 9th-PG | Coed | 830 | None |
| Christian Heritage School
| Trumbull | CT | K-12th | none | Coed | 450 | Non-Denominational Christian |
| Fairfield College Preparatory School
| Fairfield | CT | 9th-12th | none | Boys only | 925 | Roman Catholic (Jesuit) |
| Greens Farms Academy 4.6/5 based on 1 student review(s) | Greens Farms | CT | K-12th | none | Coed | 685 | None |
| Gunnery School 3.6/5 based on 1 student review(s) | Washington | CT | 9th-PG | 9th-PG | Coed | 300 | None |
| Hamden Hall Country Day School
| Hamden | CT | PK-12th | none | Coed | 565 | None |
| Holy Cross High School
| Waterbury | CT | 9th-12th | none | Coed | 760 | Roman Catholic |
| Hopkins School 5/5 based on 2 student review(s) | New Haven | CT | 7th-12th | none | Coed | 681 | None |
| Immaculate High School
| Danbury | CT | 9th-12th | none | Coed | 406 | Roman Catholic |
| Kingswood Oxford School
| West Hartford | CT | 6th-PG | none | Coed | 496 | None |
| Kolbe Cathedral High School
| Bridgeport | CT | 9th-12th | none | Coed | 308 | Roman Catholic |
| Mercy High School
| Middletown | CT | 9th-12th | none | Girls only | 700 | Roman Catholic |
| Miss Porter's School 4.1/5 based on 4 student review(s) | Farmington | CT | 9th-12th | 9th-12th | Girls only | 333 | None |
| Notre Dame Catholic High School
| Fairfield | CT | 9th-12th | none | Coed | 500 | Roman Catholic |
| Notre Dame High School
| West Haven | CT | 9th-12th | none | Boys only | 700 | Roman Catholic |
| Sacred Heart Academy
| Hamden | CT | 9th-12th | none | Girls only | 495 | Roman Catholic |
| St. Paul Catholic High School
| Briston | CT | 9th-12th | none | Coed | 300 | Roman Catholic |
| Taft School 4.3/5 based on 3 student review(s) | Watertown | CT | 9th-PG | 9th-PG | Coed | 580 | None |
| Westover School
| Middlebury | CT | 9th-12th | 9th-12th | Girls only | 193 | None |
| Wooster School
| Danbury | CT | PK-12th | none | Coed | 346 | Episcopal |
| Xavier High School
| Middletown | CT | 9th-12th | none | Boys only | 873 | Roman Catholic |