3 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Barnesville | 1 | 6,400 | 6,114 | 0.9% | 1,056 | 6 | City |
| Milner | 2 | 816 | 769 | 1.12% | 387 | 2 | City |
| Aldora | 3 | 195 | 164 | 3.17% | 771 | 0 | Town |
Barnesville is the largest city in Lamar County, with a population of 6,400.
Aldora is the smallest city in Lamar County, with a population of 195.
There are 3 cities in Lamar County, Georgia.