Strathmore High School is a privately owned school. It topped in KCSE 2018 with a mean index of 72.28. It had a total of 84 candidates.
Moi High School Kabarak came second nationally with a performance index of 72.28. It had a total of 300 candidates.
Moi Tea Girls, an extra county secondary school in Kericho County was the best among other public secondary schools.The school had a total of 136 candidates and a performance index of 69.59.
Alliance Girls, a national school performed extremely well. Out of the 399 candidates who sat for the exam, some candidates managed straight As.
BELOW IS A LIST OF TOP 20 SECONDARY SCHOOLS NATIONALLY- THEIR CATEGORY AND LOCATION:
| NAME OF SCHOOL | CATEGORY | COUNTY |
| Strathmore | Private | Nairobi |
| Moi High Schl Kabarak | Private | Nakuru |
| Moi Tea Girls | Extra County | Kericho |
| Alliance Girls | National | Kiambu |
| Alliance High | National | Kiambu |
| Mang’u High | National | Kiambu |
| Kisima Mixed Sec. | Private | Nyandarua |
| Precious Blood Riruta | Extra County | Nairobi |
| Orero Boys Sec. | Extra County | Homa Bay |
| The Kenya High | National | Nairobi |
| Moi Girls, Eldoret | National | Uasin Gishu |
| Kianda School | Private | Nairobi |
| Segero Adventist | Private | Uasin Gishu |
| Anestar Boys, Lanet | Private | Nakuru |
| Kapsabet Boys | National | Nandi |
| Starehe Girls’ | National | Nairobi |
| Maryhill Girls’ | National | Kiambu |
| Pangani Girls’ | National | Nairobi |
| Light Academy, Nairobi | Private | Nairobi |
| Sheikh Khalifa Bin Zayed-Nahyan | Private | Mombasa |
| Starehe Boys’ Centre | Private | Nairobi |
| Loreto High, Limuru | Private | Kiambu |
| · Mary Mother of Grace Sec. Schl. | National | Laikipia |
| · Maseno School | National | Kisumu |
| · Agoro Sare High | Extra County | Homa Bay |
| · Sunshine Secondary | Private | Nairobi |
| · Kyeni Girls High | Extra County | Embu |
| · Mutira Girls’ Sec. | Extra County | Kirinyaga |
| · St. Theresa’s Girls Sec. | Private | Samburu |
| · Maranda High | National | Siaya |
| · Murang’a High | National | Muranga |
| · Riara Springs Academy | Private | Nairobi |
| · Light Academy, Mombasa | Private | Mombasa |
| · Pioneer School | Private | Muranga |
| · Metkei Sec. Schl | Extra County | Elgeyo Marakwet |