| Midwest Anesthesia Partners LLC | Health Care and Social Assistance | $8,947,900 | $9,051,049 | 321 | $100.8M |  Research |
| Total Staffing Solutions INC | Administrative and Support and Waste Management | $6,485,947 | $6,574,228 | 500 | $78.7M | Research |
| Inproduction, Inc. | Real Estate and Rental and Leasing | $5,210,800 | $5,272,606 | 493 | $222.8M | Research |
| Enterprise Solutions Inc. | Administrative and Support and Waste Management | $4,215,692 | $4,263,777 | 305 | $48.0M | Research |
| Mjs Enterprises INC | Transportation and Warehousing | $3,995,637 | $4,042,818 | 144 | $55.8M | Research |
| Insurance Information Technologies, Inc. | Professional, Scientific, and Technical Services | $3,952,000 | $3,995,472 | 157 | $32.5M | Research |
| Marquette Management INC | Real Estate and Rental and Leasing | $3,654,620 | $2,909,208 | 382 | $57.3M | Research |
| Egen Solutions, Inc. | Professional, Scientific, and Technical Services | $3,461,197 | $3,501,618 | 200 | $41.4M | Research |
| West Side Tractor Sales Co. | Construction | $3,184,005 | $3,220,090 | 145 | $44.9M | Research |
| Five-Star Audiovisual, Inc. | Professional, Scientific, and Technical Services | $2,906,800 | $2,761,868 | 294 | $41.2M | Research |
| Pma Financial Network LLC | Finance and Insurance | $2,900,000 | $2,887,443 | 163 | $83.7M | Research |
| Wolf Motors of Naperville, INC | Retail Trade | $2,734,075 | $2,768,859 | 194 | $48.9M | Research |
| Route 66 Holdings LLC | Manufacturing | $2,608,200 | $2,639,571 | 139 | $34.0M | Research |
| Pace Systems, Inc, | Information | $2,476,000 | $2,507,951 | 116 | $19.5M | Research |
| Little Friends, Inc. | Health Care and Social Assistance | $2,462,000 | $1,900,512 | 417 | N/A | Research |
| Midwest Anesthesiologists, Ltd. | Health Care and Social Assistance | $2,309,800 | $2,335,657 | 66 | $20.7M | Research |
| R & J Construction Supply Co. Inc. | Real Estate and Rental and Leasing | $2,242,645 | $2,267,652 | 203 | $91.7M | Research |
| Lauterbach & Amen, LLP | Professional, Scientific, and Technical Services | $2,235,500 | $2,260,979 | 137 | $16.9M | Research |
| Sourcebooks LLC | Information | $2,171,067 | $2,196,882 | 146 | $24.5M | Research |
| Harvest Food Group, Inc. | Wholesale Trade | $2,170,000 | $2,194,352 | 218 | $56.1M | Research |
| Bill Jacobs Naperville, LLC | Retail Trade | $2,161,800 | $2,208,886 | 174 | $43.8M | Research |
| Dukane Precast Incorporated | Manufacturing | $2,062,180 | $2,086,067 | 165 | $163.7M | Research |
| Saint Patrick's Residence | Health Care and Social Assistance | $2,019,833 | $2,042,300 | 235 | N/A | Research |
| Midwest Anesthesia Partners, LLC | Health Care and Social Assistance | $2,000,000 | $2,011,444 | 263 | $82.5M | Research |
| Pace Systems Inc. | Information | $2,000,000 | $2,017,205 | 116 | $19.5M | Research |