Utility:

Ameren Energy Resources
Ameren Illinois
Aqua Illinois, Inc.
Bartlett Services, Inc.
City of Bushnell
City of Geneseo
City of Oglesby
City of Peoria
City of Peru
City of Princeton
City of Sullivan
Clean Coal Solutions
Corn Belt Energy
 

Dynegy Midwest Generation
Enerstar Power Coop
Exelon
Frontier Communications
Frontier Legacy
IBEW Local 146
IBEW Local 197
IBEW Local 601
Illinois American Water
Illinois Power Holdings
Menard Electric Coop
MJM Coop

NECA-IBEW Benefits Administration Assn.
Spoon River Coop
University of Illinois
Village of Arthur
Village of Chatham
Village of Ladd
Village of Rantoul
Village of Riverton
WICS-TV
Wireless USA
WMBD-TV

Construction:

Aclara Technologies
Acrux Cabling
Advances Electric Co.
Aldrige Electric
Asplundh Construction
Asplundh Power
Asplundh Tree Expert
Atlantic Transformer
Binion U.G. Utilities
Bodine Electric
Champaign Signal & Lighting
Coon Tree Service
Corix
Custom Underground
Davenport Electric
Davey Tree
Donoco
Egizii Electric, Inc.
Electric Power Systems
Engel Electric Co.
Ficek Electric
Gaylord Construction, Inc.
Gilbert Companies
GST Power Service Group
Haverfield Corporation

Henkels & McCoy
Hoerr Construction
Hooper
Infonet Communication
J. F. Edwards
J. F. Electric
J. H. Moore, Inc.
JMS Electric, Inc.
John Burns Construction Co.
Kafer Tiling and Ditching
Kent Power Services, LLC
L. E. Myers
Laesch Electric
LaFore
Laser Electric
Lil Rock Electric Construction, Inc.
Longfellow Drilling
Michels Power
Miller Construction
Muller & Pribyl Utilities
Myers Mechanics
Nelson Tree
Oberlander Electric Services, Co.
Okie-MO, Inc.
PAR Electric

Perlay Cable
Pieper Line
Power Services Group, Inc.
Raw Construction
Risser Electric
Ruff Electric
Sachs Electric
Serco Management Services
Shade Tree
Suarez Electric Co.
Sullivan Electric
T&F Construction
T&T Inc.
Tecam Electric
Tel Assist Comm Services, Inc.
Thorne Electric
Trans-Elect, Inc.
Tri-City Electric
Tru Check, Inc.
Underground Solutions, LLC
Utility Dynamics Corporation
Van-Mack
Wilson Construction Co.
Wright Tree