| BIBellwood Industrial LLC (former Universal Bldg Products Property) | Bellwood | IL | Chemical Manufacturing325130 | — | ◇ UNVERIFIED |
| BIBellwood Industrial Plating INC | Chicago | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| BRBelt Railway CO of Chicago | Bedford Park | IL | Chemical Manufacturing325188 | — | ◇ UNVERIFIED |
| BUBelvedere USA CORP | Belvidere | IL | Furniture and Related Product Manufacturing337127 | — | ◇ UNVERIFIED |
| BUBelvedere USA CORP | Belvidere | IL | Furniture and Related Product Manufacturing337127 | — | ◇ UNVERIFIED |
| BCBemis CO INC | Peoria | IL | Paper Manufacturing322220 | — | ◇ UNVERIFIED |
| BMBenchmark Mold Service Holdings CORP | Addison | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| BSBentley Specialties INC | Skokie | IL | Food Manufacturing311352 | — | ◇ UNVERIFIED |
| BDBenton Drumming CORP | Granite City | IL | Fabricated Metal Product Manufacturing332439 | — | ◇ UNVERIFIED |
| BPBerge Plating Work INC | Rock Island | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| BUBerger US INC | Chicago | IL | Fabricated Metal Product Manufacturing332439 | — | ◇ UNVERIFIED |
| BCBerkeley Contract Packaging | Edwardsville | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BFBerkshire Foods INC | Chicago | IL | Food Manufacturing311512 | — | ◇ UNVERIFIED |
| BMBerlin Mailing Center | Carol Stream | IL | Printing and Related Support Activities323111 | — | ◇ UNVERIFIED |
| BPBerry Plastics | Aurora | IL | Plastics and Rubber Products Manufacturing326111 | — | ◇ UNVERIFIED |
| BPBerteau-lowell Plating Plating INC | Chicago | IL | Fabricated Metal Product Manufacturing332813 | — | ◇ UNVERIFIED |
| BPBesly Products CORP | South Beloit | IL | Machinery Manufacturing333515 | — | ◇ UNVERIFIED |
| BTBestdrive Tire LLC | Jacksonville | IL | Plastics and Rubber Products Manufacturing326211 | — | ◇ UNVERIFIED |
| BGBethel Grain CO LLC | Benton | IL | Food Manufacturing311211 | — | ◇ UNVERIFIED |
| BGBevel Granite CO INC | Merrionette Park | IL | Nonmetallic Mineral Product Manufacturing327991 | — | ◇ UNVERIFIED |
| BMBeverly Manufacturing CO | Tinley Park | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BFBfc Forms Svc INC | Batavia | IL | Printing and Related Support Activities323111 | — | ◇ UNVERIFIED |
| B3Big 3 Precision Prod INC | Centralia | IL | Fabricated Metal Product Manufacturing332999 | — | ◇ UNVERIFIED |
| BBBig Beam Emergency Systems INC | Crystal Lake | IL | Electrical Equipment, Appliance & Component Manufacturing335129 | — | ◇ UNVERIFIED |
| BSBillet Specialties INC | La Grange | IL | Machinery Manufacturing333112 | — | ◇ UNVERIFIED |
| BJBill Jacobs Chevrolet Mazda | Joliet | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BMBiltrite Metal Products | Leland | IL | Fabricated Metal Product Manufacturing332999 | — | ◇ UNVERIFIED |
| BCBimet CORP | Morris | IL | Computer and Electronic Product Manufacturing334512 | — | ◇ UNVERIFIED |
| BBio-industries | Wheeling | IL | Printing and Related Support Activities323111 | — | ◇ UNVERIFIED |
| BPBio Packaging Films, LLC | Mundelein | IL | Plastics and Rubber Products Manufacturing326112 | 20-99 | ◇ UNVERIFIED |
| BFBiovantage Fuels LLC | Belvidere | IL | Chemical Manufacturing325199 | — | ◇ UNVERIFIED |
| BPBj Plastic Molding CO INC | Franklin Park | IL | Plastics and Rubber Products Manufacturing326199 | — | ◇ UNVERIFIED |
| BCBlackhawk Corrugated LLC | Carol Stream | IL | Paper Manufacturing322211 | — | ◇ UNVERIFIED |
| BLBlack Lab CORP LLC | Serena | IL | Nonmetallic Mineral Product Manufacturing327999 | — | ◇ UNVERIFIED |
| BCBlaw-knox Construction CO | Mattoon | IL | Machinery Manufacturing333120 | — | ◇ UNVERIFIED |
| BDBl Duke Metal Recycling | Forest View | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BRBleigh Ready Mix CO | Quincy | IL | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| BNBl Nickelson Iron & Metal | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BCBloomer Chocolate Company | Chicago | IL | Food Manufacturing311320 | — | ◇ UNVERIFIED |
| BNBloomington Normal Seating CO | Normal | IL | Transportation Equipment Manufacturing336360 | — | ◇ UNVERIFIED |
| BFBluegrass Folding Carton CO LLC | Elk Grove Village | IL | Wood Product Manufacturing321911 | — | ◇ UNVERIFIED |
| BLBluegrass Labels Dba Altivity | St Charles | IL | Printing and Related Support Activities323110 | — | ◇ UNVERIFIED |
| BTBluewater Thermal Solutions Chicago 1 | Northlake | IL | Fabricated Metal Product Manufacturing332811 | — | ◇ UNVERIFIED |
| BBBoarman Bros Partnership | Kincaid | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BABoasso America | Chicago | IL | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| BIBobco INC | Chicago | IL | Computer and Electronic Product Manufacturing334412 | — | ◇ UNVERIFIED |
| BPBob Propheter Construction LLC | Sterling | IL | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| BPBob Propheter Construction LLC | Utica | IL | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| BGBoc Gases | Romeoville | IL | Chemical Manufacturing325120 | — | ◇ UNVERIFIED |
| BPBodie-hoover Petroleum CORP | Lemont | IL | Petroleum and Coal Products Manufacturing324191 | — | ◇ UNVERIFIED |
