6 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Greenfield | 1 | 2,015 | 2,059 | -0.45% | 1,119 | 1.80 | City |
| Adair | 2 | 773 | 793 | -0.52% | 349 | 2.21 | City |
| Fontanelle | 3 | 661 | 683 | -0.6% | 771 | 0.86 | City |
| Orient | 4 | 350 | 364 | -0.85% | 805 | 0.43 | City |
| Diamondhead Lake | 5 | 224 | 258 | -3.86% | 230 | 0.97 | CDP |
| Bridgewater | 6 | 143 | 148 | -0.69% | 497 | 0.29 | City |
Greenfield is the largest city in Adair County, with a population of 2,015.
Bridgewater is the smallest city in Adair County.
There are 6 cities in Adair County, Iowa.