15 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Opelika | Lee County | 35,234 |
| Oxford | Calhoun County | 22,069 |
| Ozark | Dale County | 14,354 |
| Orange Beach | Baldwin County | 8,802 |
| Oneonta | Blount County | 7,031 |
| Opp | Covington County | 6,763 |
| Odenville | St. Clair County | 5,618 |
| Owens Cross Roads | Madison County | 3,107 |
| Ohatchee | Calhoun County | 1,224 |
| Our Town | Coosa County | 762 |
| Oakman | Walker County | 741 |
| Oak Grove | Clay County | 614 |
| Onycha | Coffee County | 181 |
| Orrville | Dallas County | 137 |
| Oak Hill | Wilcox County | 13 |