Illinois interconnection applications
72 electric utilities serve Illinois (EIA-861, 2025): 4 investor-owned utilitys, 41 municipal utilitys, 26 electric cooperatives, 1 state power authority. Together they serve 5,262,538 residential customers; 119,442 residential customers were on net metering at year-end 2025.
Largest utilities in Illinois
Investor-owned utility · 3,753,924 residential customers · Illinois
Applications: Own online portal – ComEd interconnection portal
Interconnection process and documents →Investor-owned utility · 1,062,810 residential customers · Illinois
Applications: PowerClerk – Ameren Illinois Interconnect (PowerClerk)
Interconnection process and documents →Investor-owned utility · 717,275 residential customers · Illinois
Applications: PDF + mail – State standard interconnection forms (IA/IL/SD)
Interconnection process and documents →Municipal utility · 59,366 residential customers · Illinois
Interconnection process and documents →Municipal utility · 57,225 residential customers · Illinois
Interconnection process and documents →Electric cooperative · 34,952 residential customers · Illinois
Interconnection process and documents →Electric cooperative · 24,414 residential customers · Illinois
Interconnection process and documents →Electric cooperative · 22,607 residential customers · Illinois
Interconnection process and documents →Electric cooperative · 18,163 residential customers · Illinois
Interconnection process and documents →Electric cooperative · 17,278 residential customers · Illinois
Interconnection process and documents →Electric cooperative · 16,203 residential customers · Illinois
Interconnection process and documents →Municipal utility · 14,901 residential customers · Illinois
Interconnection process and documents →Export compensation among the researched Illinois utilities: Net billing, NEM. Rules differ by utility – see each utility page.
Illinois interconnection rule
Illinois Commerce Commission
Interconnection rule83 Ill. Adm. Code 466 – Electric Interconnection of Distributed Energy Resources Facilities · source
Applies toElectric public utility distribution companies (ComEd, Ameren Illinois, MidAmerican, Mt. Carmel) for DER <=10 MVA not subject to FERC/RTO jurisdiction (466.10)
Application formStatewide standard forms: Appendix A Level 1 Application and Contract (v8), Appendix B Certificate of Completion, Appendix C Levels 2-4 Application, Appendix D Levels 1-4 Contract, study agreements E-G
TimelinesLevel 1: completeness 7 BD, applicant cure 10 BD, screens 15 BD, applicant 30 BD to sign (+15). Level 2: completeness 10 BD, screens 20 BD, agreement 5/30/45 BD depending on upgrades, supplemental review 30 BD. Witness test within 10 BD of commissioning or deemed waived (App. A); 15 BD notice of commissioning test (466.60(m)).
FeesLevel 1 $50; Level 2 $100+$1/kVA; Level 3 $500+$2/kVA; Level 4 $1,000+$2/kVA (Appendices A and C).
InsuranceLevel 1: proof of current homeowner's or other general liability policy; EDC named additional insured where possible (Appendix A).
External disconnectEDC may require isolation: primary-line lockable visible-break device; secondary-line lockable device with indicated status accessible to EDC; removal of self-contained meter or padlockable draw-out breaker can satisfy it (466.60(i)).
Export compensationNet billing – 220 ILCS 5/16-107.5; 83 Ill. Adm. Code 465
Customers applying/energized on or after 2025-01-01 receive credit only for the electricity supply portion (CEJA); earlier customers grandfathered at full retail; DG rebate under 16-107.6. Applies to electric utilities and alternative retail suppliers.
Municipal utilities and electric cooperatives are not ICC-jurisdictional and set their own interconnection and net metering policies.
| Level | Up to | Criteria / review / fee |
|---|---|---|
| Level 1 | 25 kW | Lab-certified inverter-based; export <=25 kW and nameplate <=50 kW (nameplate <=25 kW if export not limited); passes screens · Completeness 7 BD; screens 15 BD after complete · $50 application fee (App. A); standardized interconnection cost $200 (466.90) |
| Level 2 | 5000 kW | Lab-certified; inverter-based nameplate limited by line voltage (500 kW <5 kV, 3 MW 5-15 kV, 4 MW 15-30 kV, 5 MW 30-69 kV); synchronous/induction <=2 MW · Completeness 10 BD; screens 20 BD; agreement 5 BD (no construction) · $100 + $1.00/kVA |
| Level 3 | 10000 kW | Non-exporting: area network <=50 kW, or radial circuit with export controls (aggregate export on circuit <=10 MVA) · $500 + $2.00/kVA |
| Level 4 | 10000 kW | All others up to 10 MVA, or failed lower-level screens (studies) · $1,000 + $2.00/kVA (credited to studies) |
- 83 Ill. Adm. Code 466 (LII): https://www.law.cornell.edu/regulations/illinois/title-83/part-466 (retrieved 2026-11-13)
- 466.80 Determining the Review Level: https://www.law.cornell.edu/regulations/illinois/Ill-Admin-Code-tit-83-SS-466.80 (retrieved 2026-11-13)
- Appendix C Levels 2-4 Application: https://www.law.cornell.edu/regulations/illinois/Ill-Admin-Code-tit-83-466-app-C (retrieved 2026-11-13)
- 220 ILCS 5/16-107.5: https://ilga.gov/legislation/ilcs/documents/022000050K16-107.5.htm (retrieved 2026-11-13)
- IPA Power Hour slides (net metering 2025 transition): https://ipa.illinois.gov/content/dam/soi/en/web/ipa/documents/power-hour-7-slides-final.pdf (retrieved 2026-11-13)
All 72 utilities in Illinois
- ComEd3,753,924
- Ameren Illinois1,062,810
- MidAmerican Energy73,481
- City of Springfield59,366
- City of Naperville57,225
- Corn Belt Energy Corporation34,952
- Southwestern Electric Cooperative Inc.24,414
- Southeastern IL Electric Cooperative, Inc.22,607
- Norris Electric Cooperative18,163
- Jo-Carroll Energy, Inc.17,278
- Tri-County Electric Cooperative, Inc. (IL)16,203
- City of St Charles14,901
- Egyptian Electric Cooperative Association13,695
- Wayne-White Counties Electric Cooperative11,792
- Eastern Illinois Electric Cooperative11,001
- City of Batavia10,072
- Shelby Electric Cooperative, Inc.9,882
- Rock Energy Cooperative9,421
- Menard Electric Cooperative9,036
- City of Geneva8,675
- Coles-Moultrie Electric Cooperative8,505
- Rochelle Municipal Utilities5,993
- City of Peru4,793
- Mt. Carmel Public Utility Co4,337
- Scenic Rivers Energy Cooperative12
- Southern Illinois Electric Cooperative0
- Illinois Rural Electric Cooperative0
- M J M Electric Cooperative Inc.0
- Adams Electric Cooperative0
- Monroe County Electric Cooperative, Inc.0
- City of Highland0
- Village of Chatham0
- Clinton County Electric Cooperative, Inc.0
- Village of Rantoul0
- Rural Electric Conven Cooperative0
- City of Rock Falls0
- Enerstar Power Corporation0
- City of Waterloo0
- Village of Winnetka0
- McDonough Power Cooperative0
- Spoon River Electric Cooperative, Inc.0
- City of Princeton0
- City of Mascoutah0
- City of Geneseo0
- City of Metropolis0
- Western Illinois Electric Cooperative0
- Clay Electric Cooperative Inc.0
- City of Fairfield0
- City of Carmi0
- City of Sullivan0
- City of Marshall0
- City of Flora0
- City of Oglesby0
- City of Breese0
- City of Red Bud0
- Village of Freeburg0
- City of Carlyle0
- City of Casey0
- Village of Riverton0
- City of Newton0
- City of McLeansboro0
- City of Bushnell0
- City of Altamont0
- City of Farmer City0
- Cairo Public Utility Company0
- Village of Greenup0
- City of Roodhouse0
- Village of Bethany0
- Village of Ladd0
- City of Albany0
- University of Illinois0
- City of Allendale0
Residential customers in Illinois per EIA-861 (2025). Customer counts = bundled + delivery-only service (EIA-861 Part A + Part D). Service territory is reported by county; a county can be served by several utilities.
$500 / month
Unlimited interconnection applications. 12-month agreement, signed online. The agreement starts the day you sign; first invoice right away, then monthly.
- Unlimited interconnection applications
- Single-line diagram and site plan for every application
- Pre-submission check against the utility’s requirements
- Homeowner e-signature link for the authorization
- Filing in your utility portal accounts or by the utility’s method
- Utility questions, corrections and resubmissions
- Follow-up through approval, inspection and PTO
- Customer list, exports, API and webhooks
Applications are typically submitted within 2 business days after complete documents. Utility review times are set by each utility.