| The New York Blower Company | Manufacturing | $7,180,700 | $7,261,682 | 437 | $114.4M |  Research |
| Metro Infectious Disease Consultants Pllc | Health Care and Social Assistance | $5,440,391 | $5,516,405 | 411 | $129.0M | Research |
| Remprex Partners LLC | Transportation and Warehousing | $4,625,000 | $4,679,087 | 421 | $32.8M | Research |
| Codilis & Associates, P.c. | Professional, Scientific, and Technical Services | $4,505,200 | $4,556,917 | 332 | $90.7M | Research |
| Midtronics, INC | Manufacturing | $2,878,317 | $2,911,774 | 161 | $42.2M | Research |
| Medwest Associates INC | Wholesale Trade | $2,184,120 | $2,209,096 | 110 | $33.7M | Research |
| Bronson & Bratton, Inc. | Manufacturing | $2,093,900 | $1,775,276 | 108 | $28.3M | Research |
| Healthcare Information Services LLC | Health Care and Social Assistance | $1,896,567 | $1,913,870 | 144 | $45.2M | Research |
| Willowbrook Ford Inc. | Retail Trade | $1,796,700 | $1,809,745 | 142 | $35.8M | Research |
| Espo Engineering Corporation | Administrative and Support and Waste Management | $1,782,440 | $1,793,580 | 163 | $25.7M | Research |
| Illinois Conference of Seventh-Day Adventists | Unknown | $1,695,415 | $1,712,122 | 307 | N/A | Research |
| Derrick Enterprise INC | Transportation and Warehousing | $1,616,495 | $1,637,441 | 96 | $25.6M | Research |
| Pirrello Digital Imaging, Inc. | Professional, Scientific, and Technical Services | $1,490,100 | $1,501,814 | 191 | $22.7M | Research |
| Stone Wheel Inc. | Wholesale Trade | $1,469,200 | $1,478,525 | 225 | $68.9M | Research |
| Goebel Forming LLC | Construction | $1,465,900 | $1,474,044 | 100 | $23.1M | Research |
| Tru Fragrance & Beauty LLC | Manufacturing | $1,244,950 | $1,255,809 | 66 | $65.5M | Research |
| Morgan Harbour Construction, LLC | Construction | $1,208,700 | $1,220,357 | 63 | $71.8M | Research |
| Tru Fragrance & Beauty LLC | Manufacturing | $1,201,300 | $1,208,641 | 69 | $68.4M | Research |
| Interstate Electronics Company | Manufacturing | $1,081,155 | $1,089,564 | 57 | $14.9M | Research |
| Double Good Holdings INC | Retail Trade | $1,017,100 | $1,026,988 | 72 | $8.0M | Research |
| Lakeside Metals INC | Wholesale Trade | $1,004,914 | $1,015,211 | 70 | $21.4M | Research |
| Hinsdale Nurseries, Inc. | Administrative and Support and Waste Management | $998,591 | $1,006,940 | 108 | $23.4M | Research |
| Compass Holding, LLC | Real Estate and Rental and Leasing | $856,700 | $869,788 | 57 | $25.8M | Research |
| Pirrello Digital Imaging INC | Professional, Scientific, and Technical Services | $856,452 | $861,615 | 62 | $7.4M | Research |
| Staffing Inc. DBA Staff Illinois | Administrative and Support and Waste Management | $850,000 | $860,181 | 126 | $19.8M | Research |