| City | County | 2026 Pop. ↓ |
|---|---|---|
| Opelika | Lee County | 36,750 |
| Oxford | Calhoun County | 22,193 |
| Ozark | Dale County | 14,270 |
| Orange Beach | Baldwin County | 8,914 |
| Oneonta | Blount County | 7,045 |
| Opp | Covington County | 6,740 |
| Odenville | St. Clair County | 6,208 |
| Owens Cross Roads | Madison County | 3,458 |
| Ohatchee | Calhoun County | 1,197 |
| Oakman | Walker County | 749 |
| Our Town | Coosa County | 586 |
| Oak Grove | Clay County | 584 |
| Onycha | Coffee County | 176 |
| Orrville | Dallas County | 137 |
| Oak Hill | Wilcox County | 13 |