22 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 08540 | Princeton | 49,499 |
| 08618 | Trenton | 37,162 |
| 08610 | Trenton | 33,387 |
| 08611 | Trenton | 32,786 |
| 08648 | Lawrence Township | 31,142 |
| 08520 | Hightstown | 29,321 |
| 08619 | Trenton | 23,512 |
| 08638 | Trenton | 23,373 |
| 08550 | Princeton Junction | 20,876 |
| 08690 | Trenton | 18,996 |
| 08691 | Robbinsville | 16,924 |
| 08534 | Pennington | 13,174 |
| 08629 | Trenton | 13,015 |
| 08609 | Trenton | 13,000 |
| 08620 | Trenton | 11,949 |
| 08628 | Trenton | 9,479 |
| 08525 | Hopewell | 4,567 |
| 08544 | Princeton | 4,548 |
| 08560 | Titusville | 3,334 |
| 08542 | Princeton | 2,415 |
| 08608 | Trenton | 1,118 |
| 08561 | Windsor | 381 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 22 ZCTAs in Mercer County, New Jersey (US Census).