7 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hartsville | 1 | 7,340 | 7,438 | -0.27% | 1,225 | 6 | City |
| Darlington | 2 | 6,008 | 6,190 | -0.61% | 1,275 | 5 | City |
| Dovesville | 3 | 1,185 | 1,101 | 7.14% | 169 | 7 | CDP |
| Quinby | 4 | 893 | 901 | -0.22% | 683 | 1 | Town |
| Lamar | 5 | 850 | 855 | -0.12% | 701 | 1 | Town |
| Society Hill | 6 | 424 | 431 | -0.47% | 197 | 2 | Town |
| Lydia | 7 | 123 | 419 | -22.15% | 47 | 3 | CDP |
Hartsville is the largest city in Darlington County, with a population of 7,340.
Lydia is the smallest city in Darlington County, with a population of 123.
There are 7 cities in Darlington County, South Carolina.