11 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| James Island | Charleston County | 12,558 |
| Johnston | Edgefield County | 2,267 |
| Judson | Greenville County | 1,836 |
| Jackson | Aiken County | 1,662 |
| Joanna | Laurens County | 1,373 |
| Johnsonville | Florence County | 1,348 |
| Jonesville | Union County | 806 |
| Jefferson | Chesterfield County | 792 |
| Jacksonboro | Colleton County | 218 |
| Jamestown | Berkeley County | 73 |
| Jenkinsville | Fairfield County | 38 |