St. Clair County, Illinois
St. Clair County is the largest county in the Illinois portion of the St. Louis metropolitan area. The county seat is Belleville, a major suburb of St. Louis.
County Information
- County seat
- Belleville
Courts serving St. Clair County
- Judicial circuit
- 20th Judicial Circuit
- County seat
- Belleville
- Courthouse
- St. Clair County Courthouse
- Courthouse address
- 10 Public Square, Belleville, IL 62220
- Court telephone
- (618) 277-6600
- Chief judge
- Mary Berneking
Divisions and services listed for this court: Copier, Court Disability Coordinator, Digital Recording, E-filing Kiosk, Electronic Device Policy, Food (Vending/Other), Foreclosure Mediation Program, Internet, Lactation Rooms, Language Access, Law Library, Local Rules / Orders, Mandatory Arbitration Program, Mobile Devices Allowed, Printer, Public Transportation, Remote Proceedings, Self-Help Center.
Work and industry in St. Clair County
- BJC HealthCare — Memorial Hospital
- Empire Comfort Systems
- Peerless Premier Appliance
- Allsup
- Belleville Boot Company
- Illinois American Water — corporate office, quality control and research laboratory
- Permobil US
- Roesch Inc.
- Beno J. Gundlach Co.
- Chelar Tool & Die
- International Paper
- Triple Sticks Food Inc.
- Kaskaskia Engineering
- Mathis Marifian & Richter Ltd.
5,030 business establishments, led by retail trade (779), health care and social assistance (634), other services (573), accommodation and food services (565), construction (444). 2022 County Business Patterns.
Getting to and around St. Clair County
Interstate 55 · Interstate 64 · Interstate 70 · Interstate 255 · U.S. Highway 40 · U.S. Highway 50 · Illinois Route 3 · Illinois Route 4 · Illinois Route 13 · Illinois Route 15 · Illinois Route 111 · Illinois Route 156 · Illinois Route 157 · Illinois Route 158 · Illinois Route 159 · Illinois Route 161 · Illinois Route 163 · Illinois Route 177 · Illinois Route 203
Belleville Police Department · Scott Air Force Base · Roman Catholic Diocese of Belleville · National Shrine of Our Lady of the Snows
About St. Clair County
- Mississippi River
Community information compiled from api.census.gov, en.wikipedia.org, illinoiscourts.gov and reviewed 2026-09-10.
Legal Services in St. Clair County
Black, Ballard, McDonald, P.C. represents St. Clair County clients in the following practice areas:
St. Clair County sits in Illinois's 20th Judicial Circuit, and county matters are filed at the St. Clair County Courthouse.
Contact the Firm
The office is located in Mt. Vernon, Illinois. Contact an attorney to discuss your St. Clair County matter.