| Business | Phone |
| De Kalb Municipal Building 200 S 4th St, Dekalb 60115 | (815) 748-2096 |
| Legal Division 200 S 4th St, Dekalb 60115 | (815) 748-2093 |
| Pierce Township 14413 Perry Rd, Dekalb 60115 | (815) 286-7799 |
| Us Geological Water Resources 1420 Sycamore Rd, Dekalb 60115 | (815) 756-9207 |