| Business | Phone |
| Hillside Sewer Dept 274 Hillside Ave, Hillside 7205 | (973) 926-1110 |
| Hillside Shade Tree Dept 274 Hillside Ave, Hillside 7205 | (973) 926-1164 |
| Hillside Township Clerk 1409 Liberty Ave, Hillside 7205 | (973) 926-3000 |
| Hillside Treasurer's Office Liberty Ave & Hillside Aveamp;, Hillside 7205 | (973) 926-5051 |
| Hillside Twp Bldg Inspector 1409 Liberty Ave, Hillside 7205 | (973) 926-5100 |
| Hillside Twp Pumping Station North Ave, Hillside 7205 | (908) 354-5933 |
| Building Maintenance Dept 274 Hillside Ave, Hillside 7205 | (973) 926-3900 |