| ISIvex Specialty Paper LLC | Peoria | IL | Paper Manufacturing322120 | 20-99 | ◐ LIKELY ACTIVE |
| JPJamco Products, INC. | South Beloit | IL | Fabricated Metal Product Manufacturing332999 | 100-499 | ◐ LIKELY ACTIVE |
| JIJcg Industries INC. | Chicago | IL | Food Manufacturing311615 | — | ◐ LIKELY ACTIVE |
| JSJ.C. Schultz Enterprises Inc. Flagsource | Batavia | IL | Textile Product Mills314999 | 20-99 | ◐ LIKELY ACTIVE |
| JSJefferson Smurfit Corporation Smurfit Flexible Packaging | Schaumburg | IL | Paper Manufacturing322221 | — | ◐ LIKELY ACTIVE |
| JCJersey County Grain CO | Jerseyville | IL | Food Manufacturing311221 | — | ◐ LIKELY ACTIVE |
| JEJet Enterprises & Holding CO LLC | Sauget | IL | Primary Metal Manufacturing331410 | — | ◐ LIKELY ACTIVE |
| JCJett Cutting Service, INC. | Bedford Park | IL | Fabricated Metal Product Manufacturing332996 | 20-99 | ◐ LIKELY ACTIVE |
| JCJj Collins Sons INC | Charleston | IL | Printing and Related Support Activities323111 | — | ◐ LIKELY ACTIVE |
| JCJnr Custo-matic Screw, INC. | Glendale Heights | IL | Machinery Manufacturing333517 | 20-99 | ◐ LIKELY ACTIVE |
| JSJohn Sakash Company, INC. | Elmhurst | IL | Fabricated Metal Product Manufacturing332618 | — | ◐ LIKELY ACTIVE |
| JBJohns Byrne CO | Niles | IL | Printing and Related Support Activities323111 | — | ◐ LIKELY ACTIVE |
| JCJoliet Cabinet Co. | Crest Hill | IL | Furniture and Related Product Manufacturing337110 | 20-99 | ◐ LIKELY ACTIVE |
| JCJones Chemicals INC | Willow Springs | IL | Chemical Manufacturing325130 | — | ◐ LIKELY ACTIVE |
| KBKaluzny Bros, INC. | Joliet | IL | Food Manufacturing311613 | — | ◐ LIKELY ACTIVE |
| KCKb Cores | Kankakee | IL | Machinery Manufacturing333618 | — | ◐ LIKELY ACTIVE |
| KEKdm Enterprises L.l.c | Carpentersville | IL | Paper Manufacturing322299 | — | ◐ LIKELY ACTIVE |
| KTKenmode Tool & Engineering | Algonquin | IL | Fabricated Metal Product Manufacturing332116 | — | ◐ LIKELY ACTIVE |
| KBKerry Biofunctional Ingredients INC | Olney | IL | Food Manufacturing311999 | — | ◐ LIKELY ACTIVE |
| KVKerry/Fleischmann's Vinegar - Alton IL | Alton | IL | Food Manufacturing311941 | 1-19 | ◐ LIKELY ACTIVE |
| KMKeys Manufacturing CO INC | Paris | IL | Food Manufacturing311119 | 20-99 | ◐ LIKELY ACTIVE |
| KWKirk Wood Products | Bloomington | IL | Wood Product Manufacturing321920 | 1-19 | ◐ LIKELY ACTIVE |
| KNKitagawa Northtech, INC. | Schaumburg | IL | Fabricated Metal Product Manufacturing332710 | 20-99 | ◐ LIKELY ACTIVE |
| KSK.K. Stevens Publishing Co. | Astoria | IL | Printing and Related Support Activities323111 | 20-99 | ◐ LIKELY ACTIVE |
| KMKnapheide Manufacturing 6th & State | Quincy | IL | Transportation Equipment Manufacturing336211 | 20-99 | ◐ LIKELY ACTIVE |
| KMKnapheide Manufacturing CO | Quincy | IL | Transportation Equipment Manufacturing336211 | — | ◐ LIKELY ACTIVE |
| KTKnapheide Truck Equipment CO | Quincy | IL | Transportation Equipment Manufacturing336212 | — | ◐ LIKELY ACTIVE |
| KDKnead Dough Baking Company | Bolingbrook | IL | Food Manufacturing311812 | — | ◐ LIKELY ACTIVE |
| KKomline-Barnes | Rockford | IL | Machinery Manufacturing333999 | 100-499 | ◐ LIKELY ACTIVE |
| KGKostelac Grease Service INC | Belleville | IL | Food Manufacturing311613 | 1-19 | ◐ LIKELY ACTIVE |
| KFKraft Foods Group INC | Woodstock | IL | Food Manufacturing311421 | — | ◐ LIKELY ACTIVE |
| KRKrma Regional Treatment Facility | Kankakee | IL | Miscellaneous Manufacturing339999 | — | ◐ LIKELY ACTIVE |
| LMLa Marche Mfg CO. | Des Plaines | IL | Computer and Electronic Product Manufacturing334413 | — | ◐ LIKELY ACTIVE |
| LRLandscape Recycling Ctr | Urbana | IL | Miscellaneous Manufacturing339999 | — | ◐ LIKELY ACTIVE |
| LCLangman Construction | Rock Island | IL | Petroleum and Coal Products Manufacturing324121 | — | ◐ LIKELY ACTIVE |
| LILdi Industries - Huntley | Huntley | IL | Fabricated Metal Product Manufacturing332322 | 20-99 | ◐ LIKELY ACTIVE |
| LCLee County Landfill | Dixon | IL | Miscellaneous Manufacturing339999 | — | ◐ LIKELY ACTIVE |
| LMLeviton Manufacturing Co., INC. | Bloomingdale | IL | Electrical Equipment, Appliance & Component Manufacturing335921 | 20-99 | ◐ LIKELY ACTIVE |
| LIL&n Industries | Rushville | IL | Primary Metal Manufacturing331110 | 1-19 | ◐ LIKELY ACTIVE |
| LALombard Architectural Precast Products Company | Alsip | IL | Nonmetallic Mineral Product Manufacturing327390 | 20-99 | ◐ LIKELY ACTIVE |
| LRLubricants Rockford | Rockford | IL | Petroleum and Coal Products Manufacturing324191 | 1-19 | ◐ LIKELY ACTIVE |
| LMLudlow Manufacturing Inc. | Waukegan | IL | Fabricated Metal Product Manufacturing332322 | 20-99 | ◐ LIKELY ACTIVE |
| LPLuster Products | Chicago | IL | Chemical Manufacturing325620 | 100-499 | ◐ LIKELY ACTIVE |
| MVMackinaw Valley Powder Coating | Mackinaw | IL | Fabricated Metal Product Manufacturing332812 | — | ◐ LIKELY ACTIVE |
| MEMagna Exteriors Belvidere (2) | Belvidere | IL | Transportation Equipment Manufacturing336390 | 20-99 | ◐ LIKELY ACTIVE |
| MEMagnesium Elektron North America | Madison | IL | Primary Metal Manufacturing331420 | 20-99 | ◐ LIKELY ACTIVE |
| MMManan Medical Products INC | Wheeling | IL | Miscellaneous Manufacturing339112 | — | ◐ LIKELY ACTIVE |
| MMManan Medical Products Inc. dba Argon Medical Devices Inc. | Wheeling | IL | Miscellaneous Manufacturing339112 | 100-499 | ◐ LIKELY ACTIVE |
| MTManor Tool & Mfg CO | Schiller Park | IL | Fabricated Metal Product Manufacturing332999 | 20-99 | ◐ LIKELY ACTIVE |
| MLMarcy Laboratories INC | Glendale Heights | IL | Chemical Manufacturing325620 | — | ◐ LIKELY ACTIVE |