3 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Barnesville | 1 | 6,473 | 6,113 | 1.12% | 1,068 | 6.06 | City |
| Milner | 2 | 841 | 773 | 1.69% | 399 | 2.11 | City |
| Aldora | 3 | 199 | 163 | 3.65% | 787 | 0.25 | Town |
Barnesville is the largest city in Lamar County, with a population of 6,473.
Aldora is the smallest city in Lamar County.
There are 3 cities in Lamar County, Georgia.