Natural Gas Utilities — Illinois
Service-area summaries are high-level and do not guarantee service at a specific address. Contact the listed utility directly for address-level eligibility.
2 published results
- Ameren Illinois
Investor-Owned · Major Regulated
States served: Illinois
Customer classes: Commercial, Residential
Last confirmed: August 22, 2026
Service area (high-level): Central and southern Illinois; 816,000 natural gas customers (company service-territory page).
View utility details - Nicor Gas Company
Investor-Owned · Major Regulated
States served: Illinois
Customer classes: Commercial, Residential
Last confirmed: August 27, 2026
Service area (high-level): Natural gas distribution in northern Illinois (Ill.C.C. No. 16 gas service schedule territory).
View utility details