Althoff Catholic High School
Diocesan school · Grades 9–12
Belleville, IL
5401 W Main St, Belleville, IL 62226
Overall grade: A
ChooseAPrivateSchool.com grade, from official facts compared with similar schools.
- BClass size
- ACollege-going
- A-Years serving families
- A-Diversity
What stands out
- The largest Catholic school in Belleville
- 98% of graduates go to four-year colleges
- Serving families in Belleville since at least 2011
In Belleville, Illinois, Althoff Catholic High School is a Catholic diocesan school for students from 9th grade through 12th grade. About 335 students attend, with roughly 15 students per teacher. It has been listed in official private school records since 2011–12. The school is part of the Diocese of Belleville. The school reports that about 98% of its graduates go on to four-year colleges. The school day runs about 7 hours, 176 days a year.
At a glance
- Grades
- Grades 9–12
- Students
- 335
- Teachers
- 22.3 (full-time equivalent)
- Students per teacher
- 15
- Boys and girls
- Coed · 145 girls, 190 boys
- Religious affiliation
- Catholic · Diocesan school
- Diocese
- Diocese of Belleville
- School day
- About 7 hours
- School year
- 176 days
- Graduates going to 4-year colleges
- About 98% (the school's estimate for the class before the survey)
Reviews
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How it compares
- A smaller school: fewer students than 55% of Catholic high schools in Illinois.
- Compared with 51 Catholic high schools in Illinois.
Students by survey year
Total students reported in official records since 2011–12.
Students by grade
Student body
Member of
- National Catholic Educational Association
Questions to ask on a tour
- What is tuition, and what does it include (books, fees, uniforms, trips)?
- Do you offer financial aid, sibling discounts or payment plans?
- Do you accept ESA, voucher or tax-credit scholarship funds?
- How big are classes in my child's grade?
- What support is there for students who need extra help or more challenge?
- Is the school accredited, and by whom?
- What do a typical day and a typical week look like?
- How does the school communicate with families?
Questions about Althoff Catholic High School
What grades does Althoff Catholic High School serve?
Althoff Catholic High School serves grades 9–12.
How many students attend Althoff Catholic High School?
About 335 students, with 15 students per teacher, according to official records.
How much is tuition at Althoff Catholic High School?
Call the school to ask about tuition, financial aid and payment plans.
Official record · Updated October 2026 · Official search · Something wrong? Tell us
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