26 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 07083 | Union | 57,036 |
| 07060 | Plainfield | 47,560 |
| 07036 | Linden | 45,101 |
| 07202 | Elizabeth | 44,638 |
| 07208 | Elizabeth | 32,404 |
| 07206 | Elizabethport | 31,120 |
| 07090 | Westfield | 30,760 |
| 07065 | Rahway | 29,748 |
| 07201 | Elizabeth | 27,725 |
| 07076 | Scotch Plains | 24,667 |
| 07901 | Summit | 24,502 |
| 07016 | Cranford | 23,841 |
| 07203 | Roselle | 22,455 |
| 07205 | Hillside | 22,179 |
| 07081 | Springfield | 16,984 |
| 07066 | Clark | 15,410 |
| 07062 | Plainfield | 15,018 |
| 07063 | Plainfield | 14,533 |
| 07204 | Roselle Park | 13,965 |
| 07974 | New Providence | 12,737 |
| 07922 | Berkeley Heights | 11,971 |
| 07033 | Kenilworth | 8,339 |
| 07023 | Fanwood | 7,714 |
| 07092 | Mountainside | 6,967 |
| 07027 | Garwood | 4,688 |
| 07088 | Vauxhall | 3,083 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 26 ZCTAs in Union County, New Jersey (US Census).