36 ZIP Codes
| Zip Code | City | Population ↓ |
|---|---|---|
| 08854 | Piscataway | 61,088 |
| 08861 | Perth Amboy | 59,351 |
| 08901 | New Brunswick | 57,263 |
| 08831 | Monroe Township | 55,658 |
| 08816 | East Brunswick | 49,360 |
| 08817 | Edison | 49,020 |
| 08902 | North Brunswick | 43,932 |
| 08857 | Old Bridge | 40,891 |
| 08820 | Edison | 39,978 |
| 07747 | Matawan | 32,330 |
| 07008 | Carteret | 25,526 |
| 08859 | Parlin | 25,448 |
| 07080 | South Plainfield | 24,411 |
| 08879 | South Amboy | 23,556 |
| 08536 | Plainsboro | 20,817 |
| 07095 | Woodbridge | 20,756 |
| 08872 | Sayreville | 20,204 |
| 08830 | Iselin | 19,551 |
| 08837 | Edison | 19,437 |
| 07067 | Colonia | 18,587 |
| 08840 | Metuchen | 18,206 |
| 08852 | Monmouth Junction | 18,062 |
| 07001 | Avenel | 17,121 |
| 08882 | South River | 16,124 |
| 08904 | Highland Park | 15,121 |
| 08846 | Middlesex | 14,645 |
| 08824 | Kendall Park | 13,366 |
| 08512 | Cranbury | 12,928 |
| 08863 | Fords | 12,771 |
| 08850 | Milltown | 8,538 |
| 08884 | Spotswood | 8,187 |
| 08810 | Dayton | 7,952 |
| 07064 | Port Reading | 3,481 |
| 07077 | Sewaren | 3,248 |
| 08828 | Helmetta | 2,459 |
| 08832 | Keasbey | 2,252 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 36 ZCTAs in Middlesex County, New Jersey (US Census).