| ADAurora Distribution Center - 3m Company | Aurora | IL | Fabricated Metal Product Manufacturing332510 | — | ◇ UNVERIFIED |
| AEAurora Equipment CO | Aurora | IL | Furniture and Related Product Manufacturing337127 | — | ◇ UNVERIFIED |
| ASAurora Specialty Textiles Group INC | Aurora | IL | Textile Mills313311 | — | ◇ UNVERIFIED |
| ATAurora Transmission | Montgomery | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| ABAuto Bumper House & Parts INC | Chicago | IL | Paper Manufacturing322221 | — | ◇ UNVERIFIED |
| ATAutomotive Technology Systems | Lawrenceville | IL | Transportation Equipment Manufacturing336211 | — | ◇ UNVERIFIED |
| ACAutotrol CORP | Crystal Lake | IL | Electrical Equipment, Appliance & Component Manufacturing335312 | — | ◇ UNVERIFIED |
| ALAvante LLC | Addison | IL | Printing and Related Support Activities323110 | — | ◇ UNVERIFIED |
| ACAvatar CORP | University Park | IL | Food Manufacturing311225 | — | ◇ UNVERIFIED |
| ARAventine Renewable Energy | Canton | IL | Chemical Manufacturing325193 | — | ◇ UNVERIFIED |
| ADAvery Dennison | Mt Prospect | IL | Paper Manufacturing322220 | — | ◇ UNVERIFIED |
| ATAvicenna Technology, INC Dba Laserage | Waukegan | IL | Miscellaneous Manufacturing339112 | — | ◇ UNVERIFIED |
| AIAwmco INC | Chicago | IL | Nonmetallic Mineral Product Manufacturing327120 | — | ◇ UNVERIFIED |
| AZAw Zengeler Cleaners INC | Northbrook | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| ACAxalta Coating Systems LLC | Morton Grove | IL | Chemical Manufacturing325510 | — | ◇ UNVERIFIED |
| APAz Plastic Film | East Dundee | IL | Printing and Related Support Activities323111 | — | ◇ UNVERIFIED |
| AAztec | Chicago | IL | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| AMAztec Material Service CORP | Lockport | IL | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| AMAztec Material Service CORP | Lansing | IL | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| BPBabbitrite Products CO | Peoria | IL | Transportation Equipment Manufacturing336340 | — | ◇ UNVERIFIED |
| BBBaker's Body Repair | Chebanse | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BABall Aerosol & Specialty Container INC | Elgin | IL | Fabricated Metal Product Manufacturing332431 | — | ◇ UNVERIFIED |
| BBBallard Bros INC | White Hall | IL | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| BTBalzers Tool Coating INC | Elgin | IL | Fabricated Metal Product Manufacturing332812 | — | ◇ UNVERIFIED |
| BMBard Materials-stockton | Stockton | IL | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| BBBarlett Bituminous Asphalt LLC | Lemont | IL | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| BPBarnes Plating CORP | Chicago | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
 Barron Industries | Rockford | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| BBBartlett Bituminous Asphalt LLC | Bartlett | IL | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| BMBartlett Mfg. CO INC | Cary | IL | Computer and Electronic Product Manufacturing334412 | — | ◇ UNVERIFIED |
| BBBartlow Bros INC | Rushville | IL | Food Manufacturing311612 | — | ◇ UNVERIFIED |
| BMBase Metals Group | Alsip | IL | Primary Metal Manufacturing331419 | — | ◇ UNVERIFIED |
| BIBastian Industries | Algonquin | IL | Machinery Manufacturing333993 | — | ◇ UNVERIFIED |
| BBBattery Builders LLC | North Aurora | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BBBauer Built INC | Romeoville | IL | Plastics and Rubber Products Manufacturing326212 | — | ◇ UNVERIFIED |
| BAB Auto Parts | East St Louis | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BWBaxter & Woodman Inc- Woodstock | Woodstock | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BSBay State Milling CO | Bolingbrook | IL | Food Manufacturing311211 | — | ◇ UNVERIFIED |
| BCB-b Chemical CORP | La Grange | IL | Chemical Manufacturing325510 | — | ◇ UNVERIFIED |
| BIBeau Ind INC | Dekalb | IL | Wood Product Manufacturing321920 | — | ◇ UNVERIFIED |
| BIBee-jay Industries INC | Harwood Heights | IL | Primary Metal Manufacturing331523 | — | ◇ UNVERIFIED |
| BRBeelman Ready Mix | Sandoval | IL | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| BRBeelman Ready Mix | Mount Vernon | IL | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| BRBeelman Ready Mix | Nashville | IL | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| BIBehr Iron & Metal | Peoria | IL | Primary Metal Manufacturing331511 | — | ◇ UNVERIFIED |
| BCBell City Battery Mfg CO | Belleville | IL | Electrical Equipment, Appliance & Component Manufacturing335910 | — | ◇ UNVERIFIED |
| BRBell Racing CO | Rantoul | IL | Miscellaneous Manufacturing339920 | — | ◇ UNVERIFIED |
| BSBell Sports CO | Rantoul | IL | Miscellaneous Manufacturing339920 | — | ◇ UNVERIFIED |
| BSBell Sports INC | Rantoul | IL | Machinery Manufacturing333992 | — | ◇ UNVERIFIED |
| BEBellwood Electric Motors | Bellwood | IL | Electrical Equipment, Appliance & Component Manufacturing335312 | — | ◇ UNVERIFIED |
