13 cities
| City | County | 2025 Pop. ↓ |
|---|---|---|
| Oak Island | Brunswick County | 9,555 |
| Ogden | New Hanover County | 9,182 |
| Oxford | Granville County | 9,020 |
| Oak Ridge | Guilford County | 7,964 |
| Oakboro | Stanly County | 2,306 |
| Ocean Isle Beach | Brunswick County | 987 |
| Oriental | Pamlico County | 908 |
| Old Fort | McDowell County | 837 |
| Ocracoke | Hyde County | 657 |
| Ossipee | Alamance County | 577 |
| Old Hundred | Richmond County | 323 |
| Oak City | Martin County | 262 |
| Orrum | Robeson County | 61 |