| CCChicago Circuits CORP | Elk Grove Village | IL | Computer and Electronic Product Manufacturing334412 | — | ◇ UNVERIFIED |
| CTChicago Turnrite CO | Chicago | IL | Fabricated Metal Product Manufacturing332722 | — | ◇ UNVERIFIED |
| CMChillicothe Metal CO INC | Chillicothe | IL | Fabricated Metal Product Manufacturing332322 | — | ◇ UNVERIFIED |
| CICircom INC | Bensenville | IL | Computer and Electronic Product Manufacturing334418 | — | ◇ UNVERIFIED |
| CSCircuit Systems, INC. | Elk Grove Village | IL | Computer and Electronic Product Manufacturing334412 | — | ◇ UNVERIFIED |
| CCClariant Corporation | West Chicago | IL | Chemical Manufacturing325991 | — | ◇ UNVERIFIED |
| CACmp Anodizing INC | Elk Grove Village | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| CACnh America LLC | Goodfield | IL | Machinery Manufacturing333111 | — | ◇ UNVERIFIED |
| CCColeman Cable INC | Waukegan | IL | Primary Metal Manufacturing331422 | — | ◇ UNVERIFIED |
 Color Communications, INC. | Chicago | IL | Paper Manufacturing322220 | — | ◇ UNVERIFIED |
| CRConcentric Rockford INC | Rockford | IL | Machinery Manufacturing333996 | — | ◇ UNVERIFIED |
| CBCooper B-line INC | Highland | IL | Fabricated Metal Product Manufacturing332114 | — | ◇ UNVERIFIED |
| CBCooper B Line LLC | Pinckneyville | IL | Fabricated Metal Product Manufacturing332312 | — | ◇ UNVERIFIED |
| CCCoral Chemical CO | Waukegan | IL | Chemical Manufacturing325998 | — | ◇ UNVERIFIED |
| CSCorey Steel CO | Cicero | IL | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| CCCrown Cork & Seal CO (usa) | Aurora | IL | Fabricated Metal Product Manufacturing332431 | — | ◇ UNVERIFIED |
| CSCst Storage | Dekalb | IL | Fabricated Metal Product Manufacturing332312 | — | ◇ UNVERIFIED |
| DUDanisco Usa, INC. | Thomson | IL | Food Manufacturing311221 | — | ◇ UNVERIFIED |
| DSDdp Specialty Electronic Materials US INC | Channahon | IL | Chemical Manufacturing325211 | — | ◇ UNVERIFIED |
| DFDekalb Forge CO | Dekalb | IL | Fabricated Metal Product Manufacturing332111 | — | ◇ UNVERIFIED |
| DCDeltrol CORP | Bellwood | IL | Fabricated Metal Product Manufacturing332912 | — | ◇ UNVERIFIED |
| DMDiagraph Marking and Coding | Frankfort | IL | Paper Manufacturing322220 | — | ◇ UNVERIFIED |
| DRDiesel Radiator CO | Melrose Park | IL | Fabricated Metal Product Manufacturing332999 | — | ◇ UNVERIFIED |
| DCDober Chemical CORP | Glenwood | IL | Chemical Manufacturing325612 | — | ◇ UNVERIFIED |
| DIDober Innovation & Technology | Woodridge | IL | Chemical Manufacturing325612 | — | ◇ UNVERIFIED |
| DCDynaburr Chicago INC | Northlake | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| DNDyno Nobel INC | Barry | IL | Chemical Manufacturing325920 | — | ◇ UNVERIFIED |
 Eagle Capital Group, LLC. D/b/a Summit Interconnect Chicago | Schaumburg | IL | Computer and Electronic Product Manufacturing334412 | — | ◇ UNVERIFIED |
| ESEast Side Jersey Dairy - O'fallon, Il | O'fallon | IL | Food Manufacturing311511 | — | ◇ UNVERIFIED |
| ECEaton CORP | Lincoln | IL | Electrical Equipment, Appliance & Component Manufacturing335311 | — | ◇ UNVERIFIED |
| EIEcolab INC | Roscoe | IL | Machinery Manufacturing333248 | — | ◇ UNVERIFIED |
| EFEconomy Fasteners INC | Rockford | IL | Fabricated Metal Product Manufacturing332811 | — | ◇ UNVERIFIED |
| EIEcp INC | Woodridge | IL | Chemical Manufacturing325611 | — | ◇ UNVERIFIED |
| EMEdsal Mfg CO INC | Chicago | IL | Fabricated Metal Product Manufacturing332119 | — | ◇ UNVERIFIED |
| EPElastomer Processing Group - Chicago | Chicago | IL | Plastics and Rubber Products Manufacturing326299 | — | ◇ UNVERIFIED |
| ECElectri-flex CO | Roselle | IL | Electrical Equipment, Appliance & Component Manufacturing335932 | — | ◇ UNVERIFIED |
| ESElgiloy Specialty Metals | Hampshire | IL | Primary Metal Manufacturing331221 | — | ◇ UNVERIFIED |
| EMElkay Manufacturing CO | Savanna | IL | Machinery Manufacturing333415 | — | ◇ UNVERIFIED |
| EMElkay Manufacturing CO | Lanark | IL | Fabricated Metal Product Manufacturing332913 | — | ◇ UNVERIFIED |
| EMElkay Mfg | Broadview | IL | Fabricated Metal Product Manufacturing332999 | — | ◇ UNVERIFIED |
| ECEllwood Chrome Crankshaft CO LLC | Joliet | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| EHEmpire Hard Chrome | Chicago | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| EHEmpire Hard Chrome INC | Chicago | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| EIEmulsicoat, INC. | Urbana | IL | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| EPEn-chro Plating LTD | Melrose Park | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| EIEnduro Industries INC. | Addison | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| EPEngineered Polymer Solutions Dba Valspar Coatings | Chicago Heights | IL | Chemical Manufacturing325510 | — | ◇ UNVERIFIED |
| EPEngineered Polymer Solutions Dba Valspar Coatings | Matteson | IL | Chemical Manufacturing325510 | — | ◇ UNVERIFIED |
| ESEster Solutions | Bedford Park | IL | Chemical Manufacturing325199 | — | ◇ UNVERIFIED |
| EIEvapco INC | Newton | IL | Textile Mills313320 | — | ◇ UNVERIFIED |
