The average private high school endowment in Illinois is $36.8M (2026-27).
The private high school in Illinois with the highest endowment is Francis W. Parker School, with a endowment of $68M.
Quick Facts (2026-27)
- # IL Schools Ranked: 9
- Top 20 Range (Endowment): $2–$68
- IL School Avg.: $22
- National School Avg.: $35





