19 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Pennsville | 1 | 12,928 | 12,679 | 0.57% | 608 | 21 | Township |
| Pittsgrove | 2 | 9,042 | 8,779 | 0.78% | 201 | 45 | Township |
| Carneys Point | 3 | 8,736 | 8,635 | 0.49% | 517 | 17 | Township |
| Salem | 4 | 5,403 | 5,301 | 0.63% | 2,305 | 2 | City |
| Salem | 5 | 5,386 | 5,301 | 0.32% | 2,298 | 2 | City |
| Penns Grove | 6 | 4,956 | 4,857 | 0.71% | 5,550 | 1 | Borough |
| Penns Grove | 7 | 4,937 | 4,857 | 0.33% | 5,529 | 1 | Borough |
| Pilesgrove | 8 | 4,302 | 4,186 | 0.82% | 123 | 35 | Township |
| Woodstown | 9 | 3,783 | 3,681 | 0.69% | 2,402 | 2 | Borough |
| Woodstown | 10 | 3,776 | 3,681 | 0.51% | 2,397 | 2 | Borough |
| Upper Pittsgrove | 11 | 3,544 | 3,434 | 1.06% | 88 | 40 | Township |
| Alloway | 12 | 3,342 | 3,269 | 0.45% | 100 | 33 | Township |
| Quinton | 13 | 2,660 | 2,586 | 0.72% | 112 | 24 | Township |
| Oldmans | 14 | 1,960 | 1,910 | 0.72% | 100 | 20 | Township |
| Lower Alloways Creek | 15 | 1,762 | 1,718 | 0.69% | 39 | 45 | Township |
| Mannington | 16 | 1,490 | 1,464 | 0.95% | 44 | 34 | Township |
| Elmer | 17 | 1,386 | 1,343 | 0.65% | 1,559 | 1 | Borough |
| Elmer | 18 | 1,385 | 1,343 | 0.58% | 1,558 | 1 | Borough |
| Elsinboro | 19 | 1,025 | 1,001 | 0.89% | 86 | 12 | Township |
Pennsville is the largest city in Salem County, with a population of 12,928.
Elsinboro is the smallest city in Salem County, with a population of 1,025.
There are 19 cities in Salem County, New Jersey.