| RARadiac Abrasives - Oswego | Oswego | IL | Nonmetallic Mineral Product Manufacturing327910 | 20-99 | ● ACTIVE |
| RPRandolph Packing CO | Streamwood | IL | Food Manufacturing311612 | 100-499 | ● ACTIVE |
| RCRauland-borg CORP | Mount Prospect | IL | Computer and Electronic Product Manufacturing334290 | — | ● ACTIVE |
Ravenswood Studio INC | Lincolnwood | IL | Machinery Manufacturing333414 | 100-499 | ● ACTIVE |
Reaco Battery Service CORP | Johnston City | IL | Electrical Equipment, Appliance & Component Manufacturing335910 | 20-99 | ● ACTIVE |
Recycled Rubber Products Distributors, LLC | Joliet | IL | Miscellaneous Manufacturing339999 | 20-99 | ● ACTIVE |
Red Maple Manufacturing, INC | East Saint Louis | IL | Miscellaneous Manufacturing339991 | 1-19 | ● ACTIVE |
| RTRegis Technologies INC | Morton Grove | IL | Chemical Manufacturing325199 | 20-99 | ● ACTIVE |
| RPReliable Plating CORP | Chicago | IL | Fabricated Metal Product Manufacturing332813 | — | ● ACTIVE |
| ROReliance Orthodontic Products, INC. | Itasca | IL | Miscellaneous Manufacturing339114 | 20-99 | ● ACTIVE |
Reliance Specialty Products INC | Carol Stream | IL | Chemical Manufacturing325998 | 1-19 | ● ACTIVE |
Remco Technology, INC | Skokie | IL | Plastics and Rubber Products Manufacturing326140 | 20-99 | ● ACTIVE |
| RIRenishaw, INC. | West Dundee | IL | Computer and Electronic Product Manufacturing334513 | — | ● ACTIVE |
Ribbon Webbing CORP | Chicago | IL | Textile Mills313220 | 100-499 | ● ACTIVE |
| RWRichard Wolf Medical Instruments CORP | Vernon Hills | IL | Miscellaneous Manufacturing339112 | 100-499 | ● ACTIVE |
Rieke Office Interiors INC | Elgin | IL | Furniture and Related Product Manufacturing337211 | 20-99 | ● ACTIVE |
| RCRobert C. Weisheit CO INC | Glendale Heights | IL | Fabricated Metal Product Manufacturing332710 | 20-99 | ● ACTIVE |
| RFRochelle Foods LLC | Rochelle | IL | Food Manufacturing311612 | 500+ | ● ACTIVE |
Rockford Ball Screw Company | Rockford | IL | Fabricated Metal Product Manufacturing332710 | 20-99 | ● ACTIVE |
Rock River Arms INC | Colona | IL | Fabricated Metal Product Manufacturing332994 | 20-99 | ● ACTIVE |
| RCRogan Corporation | Northbrook | IL | Plastics and Rubber Products Manufacturing326199 | 20-99 | ● ACTIVE |
| RIRoho INC | Belleville | IL | Plastics and Rubber Products Manufacturing326199 | — | ● ACTIVE |
Roth Pump CO | Milan | IL | Machinery Manufacturing333911 | 20-99 | ● ACTIVE |
Round Ground Metals, INC. | Hanover Park | IL | Primary Metal Manufacturing331110 | 100-499 | ● ACTIVE |
Ryan Metal Products INC | Kankakee | IL | Fabricated Metal Product Manufacturing332999 | 20-99 | ● ACTIVE |
| SISabic Innovative Plastics US LLC | Ottawa | IL | Chemical Manufacturing325211 | 100-499 | ● ACTIVE |
Safety Storage, INC | Charleston | IL | Fabricated Metal Product Manufacturing332311 | 20-99 | ● ACTIVE |
Saliba Industries Holdings, LLC | Waukegan | IL | Fabricated Metal Product Manufacturing332710 | 1-19 | ● ACTIVE |
Sandstrom Products Company | Port Byron | IL | Chemical Manufacturing325510 | 20-99 | ● ACTIVE |
Saporito Finishing CO | Cicero | IL | Fabricated Metal Product Manufacturing332813 | 100-499 | ● ACTIVE |
Sauber Manufacturing CO | Virgil | IL | Transportation Equipment Manufacturing336212 | 20-99 | ● ACTIVE |
| SBSb Boron Corporation | Bellwood | IL | Chemical Manufacturing325180 | 1-19 | ● ACTIVE |
S&c Electric Company | Chicago | IL | Electrical Equipment, Appliance & Component Manufacturing335313 | — | ● ACTIVE |
Schmid Tool & Engineering CORP | Villa Park | IL | Fabricated Metal Product Manufacturing332710 | — | ● ACTIVE |
Scot Forge Company | Spring Grove | IL | Fabricated Metal Product Manufacturing332111 | 500+ | ● ACTIVE |
Seating Concepts INC | Rockdale | IL | Plastics and Rubber Products Manufacturing326199 | 100-499 | ● ACTIVE |
| SFSenior Flexonics | Bartlett | IL | Fabricated Metal Product Manufacturing332999 | 100-499 | ● ACTIVE |
Servi-sure, LLC | Chicago | IL | Fabricated Metal Product Manufacturing332999 | 20-99 | ● ACTIVE |
Sewer Equipment CO. of America | Dixon | IL | Machinery Manufacturing333120 | 100-499 | ● ACTIVE |
Siemens Manufacturing CO INC | Freeburg | IL | Computer and Electronic Product Manufacturing334416 | 100-499 | ● ACTIVE |
Sievert Electric Service and Sales Company | Forest Park | IL | Machinery Manufacturing333923 | 20-99 | ● ACTIVE |
Sign Works INC | Bensenville | IL | Printing and Related Support Activities323111 | 1-19 | ● ACTIVE |
| SMSipi Metals CORP | Chicago | IL | Primary Metal Manufacturing331410 | 100-499 | ● ACTIVE |
S.i. Tech INC | Batavia | IL | Computer and Electronic Product Manufacturing334290 | 1-19 | ● ACTIVE |
Sko-die, LLC | Morton Grove | IL | Fabricated Metal Product Manufacturing332999 | 20-99 | ● ACTIVE |
| SISkolnik Industries LLC | Chicago | IL | Fabricated Metal Product Manufacturing332439 | 100-499 | ● ACTIVE |
| SVSloan Valve CO | Franklin Park | IL | Fabricated Metal Product Manufacturing332913 | 500+ | ● ACTIVE |
Smalley Steel Ring CO. | Lake Zurich | IL | Fabricated Metal Product Manufacturing332613 | 500+ | ● ACTIVE |
| SMS & M Group INC | Wood Dale | IL | Computer and Electronic Product Manufacturing334418 | 20-99 | ● ACTIVE |
| SPSmithfield Packaged Meats CORP | Saint Charles | IL | Food Manufacturing311611 | 100-499 | ● ACTIVE |