6 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Greenfield | 1 | 1,969 | 2,062 | -0.96% | 1,093 | 2 | City |
| Adair | 2 | 792 | 792 | 0% | 358 | 2 | City |
| Fontanelle | 3 | 683 | 687 | -0.15% | 797 | 1 | City |
| Orient | 4 | 362 | 364 | -0.28% | 832 | 0 | City |
| Diamondhead Lake | 5 | 224 | 258 | -3.86% | 230 | 1 | CDP |
| Bridgewater | 6 | 145 | 145 | 0% | 503 | 0 | City |
Greenfield is the largest city in Adair County, with a population of 1,969.
Bridgewater is the smallest city in Adair County, with a population of 145.
There are 6 cities in Adair County, Iowa.