| Name | Phone | Category |
| FARMERS INSURANCE-GREG PROCOPIO | (630) 968-1666 | Insurance |
| FAST & FRESH LAUNDRY | (630) 474-3890 | Laundromat |
| FASTSIGNS | (630) 984-0101 | Signs |
| FEEL GOOD YARD CARDS | (630) 310-9274 | |
| LAW OFFICE OF EILEEN R. FITZGERALD | (630) 493-4380 | Attorneys - Consumer |
| FLAVORCHEM CORPORATION | (630) 932-8100 | Manufacturers |
| FLINT ARCHITECTS | (630) 953-9220 | Architects |
| FLOOD BROTHERS DISPOSAL | (630) 261-0400 | Waste and Recycling Services |
| FOOT & ANKLE WELLNESS CENTER AT SEVEN BRIDGES | (630) 852-8522 | Foot and Ankle Services |
| Forensic Analytical Consulting Services, Inc | 630-642-8111 | |
| FRESH THYME FARMERS MARKET | (331) 251-7100 | |
| FRESH THYME FARMERS MARKET | 312-709-3247 | |
| FUSIBOND PIPING SYSTEMS INC. | (630) 969-4488 | |