15 cities
| City | County | 2026 Pop. ↓ |
|---|---|---|
| Opelika | Lee County | 36,972 |
| Oxford | Calhoun County | 22,088 |
| Ozark | Dale County | 14,385 |
| Orange Beach | Baldwin County | 8,834 |
| Oneonta | Blount County | 7,087 |
| Opp | Covington County | 6,684 |
| Odenville | St. Clair County | 6,087 |
| Owens Cross Roads | Madison County | 3,415 |
| Ohatchee | Calhoun County | 1,220 |
| Oakman | Walker County | 747 |
| Oak Grove | Clay County | 598 |
| Our Town | Coosa County | 586 |
| Onycha | Coffee County | 179 |
| Orrville | Dallas County | 134 |
| Oak Hill | Wilcox County | 9 |