11 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Seneca | 1 | 9,167 | 8,856 | 0.68% | 1,112 | 8.24 | City |
| Walhalla | 2 | 4,277 | 4,081 | 0.92% | 1,101 | 3.88 | City |
| Keowee Key | 3 | 3,824 | 2,757 | 7.14% | 1,103 | 3.47 | CDP |
| Westminster | 4 | 2,453 | 2,353 | 0.82% | 712 | 3.45 | City |
| Utica | 5 | 1,695 | 1,761 | 0.77% | 1,497 | 1.13 | CDP |
| Fair Play | 6 | 546 | 282 | -1.62% | 81 | 6.77 | CDP |
| West Union | 7 | 392 | 374 | 1.03% | 494 | 0.79 | Town |
| Newry | 8 | 383 | 98 | 3.79% | 1,298 | 0.29 | CDP |
| Salem | 9 | 125 | 120 | 0.81% | 137 | 0.92 | Town |
| Tamassee | 10 | 102 | 149 | 6.25% | 88 | 1.17 | CDP |
| Longcreek | 11 | 36 | 36 | 5.88% | 19 | 1.90 | CDP |
Seneca is the largest city in Oconee County, with a population of 9,167.
Longcreek is the smallest city in Oconee County.
There are 11 cities in Oconee County, South Carolina.