| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Centerville | 1 | 5,310 | 5,407 | -0.32% | 1,098 | 5 | City |
| Moravia | 2 | 623 | 638 | -0.48% | 530 | 1 | City |
| Moulton | 3 | 592 | 606 | -0.5% | 594 | 1 | City |
| Mystic | 4 | 314 | 322 | -0.63% | 107 | 3 | City |
| Cincinnati | 5 | 280 | 287 | -0.71% | 159 | 2 | City |
| Exline | 6 | 153 | 159 | -0.65% | 154 | 1 | City |
| Unionville | 7 | 73 | 76 | -1.35% | 97 | 1 | City |
| Numa | 8 | 70 | 72 | -1.41% | 159 | 0 | City |
| Plano | 9 | 56 | 58 | -1.75% | 100 | 1 | City |
| Rathbun | 10 | 39 | 41 | -2.5% | 177 | 0 | City |
| Udell | 11 | 30 | 32 | -3.23% | 107 | 0 | City |
Centerville is the largest city in Appanoose County, with a population of 5,310.
Udell is the smallest city in Appanoose County, with a population of 30.
There are 11 cities in Appanoose County, Iowa.