5 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hartsville | 1 | 7,321 | 7,438 | -0.26% | 1,222 | 6 | City |
| Darlington | 2 | 5,972 | 6,190 | -0.6% | 1,267 | 5 | City |
| Quinby | 3 | 892 | 901 | -0.11% | 682 | 1 | Town |
| Lamar | 4 | 849 | 855 | -0.12% | 700 | 1 | Town |
| Society Hill | 5 | 423 | 431 | -0.24% | 176 | 2 | Town |
Hartsville is the largest city in Darlington County, with a population of 7,321.
Society Hill is the smallest city in Darlington County, with a population of 423.
There are 5 cities in Darlington County, South Carolina.