| AAAllied Asphalt Paving CO | West Chicago | IL | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| AAAllied Asphalt Paving CO | Franklin Park | IL | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| ADAllied Die Casting CORP | Mchenry | IL | Primary Metal Manufacturing331491 | — | ◇ UNVERIFIED |
| AHAllied Hastings Barrel Drum Service | Chicago | IL | Fabricated Metal Product Manufacturing332439 | — | ◇ UNVERIFIED |
| ATAllied Tube & Conduit | South Holland | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| ATAllied Tube & Conduit | Harvey | IL | Machinery Manufacturing333618 | — | ◇ UNVERIFIED |
| AWAllied Welding, INC. | Chillicothe | IL | Fabricated Metal Product Manufacturing332710 | 20-99 | ◇ UNVERIFIED |
| AMAll Metals Recycling | Franklin Park | IL | Fabricated Metal Product Manufacturing332812 | — | ◇ UNVERIFIED |
| AIAlloyweld Inspection | Bensenville | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| APAll Printing & Graphics INC | Broadview | IL | Printing and Related Support Activities323110 | — | ◇ UNVERIFIED |
| ASAll Spun Metal Products | Des Plaines | IL | Fabricated Metal Product Manufacturing332111 | — | ◇ UNVERIFIED |
| AFAlpha Feed Mill INC | Alpha | IL | Food Manufacturing311119 | — | ◇ UNVERIFIED |
| ACAltamont CO | Rantoul | IL | Wood Product Manufacturing321211 | — | ◇ UNVERIFIED |
| AEAlternative Energy Sources INC | Greenville | IL | Chemical Manufacturing325193 | — | ◇ UNVERIFIED |
 Altium Packaging | West Chicago | IL | Plastics and Rubber Products Manufacturing326160 | — | ◇ UNVERIFIED |
| AKAltman & Koehler Foundry CO INC | Chicago | IL | Primary Metal Manufacturing331524 | — | ◇ UNVERIFIED |
| ARAltman Ron | Chicago | IL | Primary Metal Manufacturing331524 | — | ◇ UNVERIFIED |
| AMAlton Materials | Alton | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| AIAltorfer INC | Peoria | IL | Electrical Equipment, Appliance & Component Manufacturing335312 | — | ◇ UNVERIFIED |
| AIAltrachem INC | Joliet | IL | Fabricated Metal Product Manufacturing332312 | — | ◇ UNVERIFIED |
| AAlumetco | Chicago | IL | Primary Metal Manufacturing331420 | — | ◇ UNVERIFIED |
| AIAlvar INC | Washburn | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| AAAlways Aluminum | Rockford | IL | Primary Metal Manufacturing331524 | — | ◇ UNVERIFIED |
| APAmax Plating Incorporated | Elgin | IL | Fabricated Metal Product Manufacturing332812 | — | ◇ UNVERIFIED |
| ASAmazon.com Services LLC Hmw1 | Wilmington | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| AEAmber Engineering & Mfg CO | Elk Grove Village | IL | Fabricated Metal Product Manufacturing332812 | — | ◇ UNVERIFIED |
| APAmber Plating Works INC | Chicago | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| AAAmbraw Asphalt Materials INC | Lawrenceville | IL | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| AIAmcast INC | Bensenville | IL | Primary Metal Manufacturing331523 | — | ◇ UNVERIFIED |
| AEAmco Engineering CO | Schiller Park | IL | Primary Metal Manufacturing331210 | — | ◇ UNVERIFIED |
| AAAmcor American Metal Chem CORP | Chicago | IL | Chemical Manufacturing325998 | — | ◇ UNVERIFIED |
| ACAmcor Corporation | Batavia | IL | Plastics and Rubber Products Manufacturing326199 | — | ◇ UNVERIFIED |
| AFAmcor Flexibles Healthcare INC | Mundelein | IL | Plastics and Rubber Products Manufacturing326112 | — | ◇ UNVERIFIED |
| AFAmcor Flexibles NA | Batavia | IL | Paper Manufacturing322220 | — | ◇ UNVERIFIED |
| ARAmcor Rigid Plastics | Itasca | IL | Plastics and Rubber Products Manufacturing326160 | — | ◇ UNVERIFIED |
| ARAmcor Rigid Plastics USA INC | Des Plaines | IL | Plastics and Rubber Products Manufacturing326199 | — | ◇ UNVERIFIED |
| ARAmcor Rigid Plastics USA LLC | Addison | IL | Plastics and Rubber Products Manufacturing326160 | — | ◇ UNVERIFIED |
| AEAmeren - Elgin Energy Center | Elgin | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| ARAmerenenergy Resouces Generating CO | Peoria | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| AMAmerica Material Sales | Maywood | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| AAAmerican Allied Rail | Washington | IL | Transportation Equipment Manufacturing336510 | — | ◇ UNVERIFIED |
| ABAmerican Blending and Filling | Waukegan | IL | Chemical Manufacturing325612 | — | ◇ UNVERIFIED |
| ABAmerican Blending and Filling | Waukegan | IL | Chemical Manufacturing325612 | — | ◇ UNVERIFIED |
| ACAmerican Cast Films INC | Wheeling | IL | Plastics and Rubber Products Manufacturing326113 | — | ◇ UNVERIFIED |
| ACAmerican Circuit Systems Incorporated | Addison | IL | Computer and Electronic Product Manufacturing334412 | — | ◇ UNVERIFIED |
| ACAmerican Colloid CO | Granite City | IL | Nonmetallic Mineral Product Manufacturing327992 | — | ◇ UNVERIFIED |
| ADAmerican Decal & Mfg CO | Chicago | IL | Printing and Related Support Activities323110 | — | ◇ UNVERIFIED |
| ADAmerican Demolition CORP | La Grange Park | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| AFAmerican Flange & Manufacturing CO INC | Carol Stream | IL | Paper Manufacturing322214 | — | ◇ UNVERIFIED |
| AGAmerican Gasket and Rubber CO | Schiller Park | IL | Plastics and Rubber Products Manufacturing326291 | — | ◇ UNVERIFIED |
