13 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Old Bridge township | Middlesex County | 68,947 |
| Ocean township | Monmouth County | 27,518 |
| Oakland borough | Bergen County | 12,746 |
| Ocean City city | Cape May County | 11,130 |
| Ocean township | Ocean County | 9,111 |
| Oradell borough | Bergen County | 8,236 |
| Old Tappan borough | Bergen County | 6,550 |
| Oceanport borough | Monmouth County | 6,306 |
| Oaklyn borough | Camden County | 3,972 |
| Oxford township | Warren County | 2,480 |
| Ogdensburg borough | Sussex County | 2,315 |
| Ocean Gate borough | Ocean County | 2,007 |
| Oldmans township | Salem County | 1,942 |