Post Offices List in Hillside City, New Jersey:
| Hillside Post Office | 1146 Liberty Ave, Hillside, NJ 07205 |
| Industrial Hillside Post Office | 397 Hillside Ave, Hillside, NJ 07205 |
| Hillside Post Office | 1146 Liberty Ave, Hillside, NJ 07205 |
| Industrial Hillside Post Office | 397 Hillside Ave, Hillside, NJ 07205 |