Exhibit 21
SUBSIDIARIES OF AMEREN CORPORATION
AT DECEMBER 31, 2005
| Name | State or Jurisdiction of Incorporation | |
Ameren Corporation | Missouri | |
Ameren Development Company | Missouri | |
Ameren Energy Communications, Inc. | Missouri | |
Ameren ERC, Inc. | Missouri | |
Missouri Central Railroad Company | Delaware | |
Gateway Energy Systems, L.C. | Missouri | |
Gateway Energy WGK Project, L.L.C. | Missouri | |
Ameren Energy, Inc. | Missouri | |
Ameren Energy Resources Company | Illinois | |
Ameren Energy Development Company | Illinois | |
Ameren Energy Generating Company | Illinois | |
Coffeen and Western Railroad Company | Illinois | |
Ameren Energy Marketing Company | Illinois | |
Illinois Materials Supply Co. | Illinois | |
Electric Energy, Inc. (40% interest) | Illinois | |
Midwest Electric Power Inc. | Illinois | |
Joppa and Eastern Railroad Company | Illinois | |
Met South, Inc. | Illinois | |
Massac Enterprises LLC | Illinois | |
Joppa Generating Station LLC | Illinois | |
Southern Materials Transfer, Inc. | Illinois | |
AmerenEnergy Medina Valley Cogen, (No. 4) L.L.C. | Illinois | |
AmerenEnergy Medina Valley Operations, L.L.C. | Illinois | |
AmerenEnergy Medina Valley Cogen (No. 2) L.L.C. | Illinois | |
AmerenEnergy Medina Valley Cogen, L.L.C. | Illinois | |
Ameren Energy Fuels and Services Company | Illinois | |
Cowboy Railroad Development Co. | Arkansas | |
AFS Development Company, LLC | Illinois | |
Gateway Terminal LLC | Missouri | |
CLM LLC - VII | Delaware | |
CLM LLC - VIII | Delaware | |
CILCORP Lease Management LLC | Delaware | |
Ameren Services Company | Missouri | |
Central Illinois Public Service Company | Illinois | |
CIPS Energy Inc. | Illinois | |
CIPSCO Investment Company | Illinois | |
CIPSCO Securities Company | Illinois | |
CIPSCO Leasing Company | Illinois | |
CLC Aircraft Leasing Company | Illinois | |
CLC Leasing Company A | Illinois | |
CIPSCO Energy Company | Illinois | |
CEC-ACLP Co. | Illinois | |
CIPSCO Ventures Company | Illinois |
SUBSIDIARIES OF AMEREN CORPORATION
AT DECEMBER 31, 2005
| Name | State or Jurisdiction of Incorporation | |
Union Electric Company | Missouri | |
Union Electric Development Corporation | Missouri | |
Electric Energy, Inc. (40% interest) | Illinois | |
Midwest Electric Power Inc. | Illinois | |
Joppa and Eastern Railroad Company | Illinois | |
Met South, Inc. | Illinois | |
Massac Enterprises LLC | Illinois | |
Joppa Generating Station LLC | Illinois | |
Southern Materials Transfer, Inc. | Illinois | |
CILCORP INC. | Illinois | |
Central Illinois Light Company | Illinois | |
CILCO Exploration and Development Co. | Illinois | |
AmerenEnergy Resources Generating Company | Illinois | |
CIM Leasing LLC | Delaware | |
CILCO Energy Corporation | Illinois | |
CIM Energy Investments Inc. | Illinois | |
QST Enterprises Inc. | Illinois | |
QST Energy Inc. | Illinois | |
QST Energy Trading Inc. | Illinois | |
CILCORP Infraservices Inc. | Illinois | |
QST Inc. | Illinois | |
ESE Land Corporation | Illinois | |
Savannah Resources Corp. | California | |
ESE Placentia Development Corporation | Illinois | |
California/Nevada Development L.L.C. | Delaware | |
CILCORP Ventures Inc. | Illinois | |
CILCORP Energy Services Inc. | Illinois | |
Agricultural Research & Development Corp. | Illinois | |
Peoria Medical Research Corp. | Illinois | |
Illinois Power Company | Illinois | |
IP Gas Supply Company | Illinois | |
Illinois Power Transmission Company, LLC | Delaware | |
Illinois Power Securitization Limited Liability Company | Delaware | |
Illinois Power Special Purpose Trust | Delaware | |
Illinois Power Financing I | Delaware | |
Illinois Power Financing II | Delaware |