15 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Mount Pleasant | 1 | 97,780 | 91,251 | 1.13% | 1,969 | 50 | Town |
| James Island | 2 | 12,666 | 12,020 | 0.86% | 2,670 | 5 | Town |
| Hollywood | 3 | 5,607 | 5,294 | 0.94% | 239 | 24 | Town |
| Isle of Palms | 4 | 4,391 | 4,348 | 0.16% | 990 | 4 | City |
| Ravenel | 5 | 2,756 | 2,552 | 1.25% | 209 | 13 | Town |
| Seabrook Island | 6 | 2,175 | 2,055 | 0.93% | 366 | 6 | Town |
| Folly Beach | 7 | 2,088 | 2,076 | 0.1% | 167 | 13 | City |
| Kiawah Island | 8 | 1,997 | 2,014 | -0.15% | 179 | 11 | Town |
| Sullivan's Island | 9 | 1,974 | 1,896 | 0.66% | 790 | 2 | Town |
| Awendaw | 10 | 1,503 | 1,409 | 1.08% | 87 | 17 | Town |
| Meggett | 11 | 1,482 | 1,394 | 1.02% | 82 | 18 | Town |
| Lincolnville | 12 | 1,240 | 1,156 | 1.14% | 1,032 | 1 | Town |
| Edisto Beach | 13 | 1,076 | 1,028 | 0.75% | 505 | 2 | Town |
| McClellanville | 14 | 636 | 606 | 0.79% | 285 | 2 | Town |
| Rockville | 15 | 143 | 136 | 0.7% | 337 | 0 | Town |
Mount Pleasant is the largest city in Charleston County, with a population of 97,780.
Rockville is the smallest city in Charleston County, with a population of 143.
There are 15 cities in Charleston County, South Carolina.