| City | County | 2026 Pop. ↓ |
|---|---|---|
| Oak Island | Brunswick County | 9,568 |
| Oxford | Granville County | 9,046 |
| Ogden | New Hanover County | 8,732 |
| Oak Ridge | Guilford County | 7,951 |
| Oakboro | Stanly County | 2,353 |
| Ocean Isle Beach | Brunswick County | 965 |
| Oriental | Pamlico County | 915 |
| Old Fort | McDowell County | 801 |
| Ocracoke | Hyde County | 654 |
| Ossipee | Alamance County | 585 |
| Oak City | Martin County | 264 |
| Old Hundred | Richmond County | 253 |
| Orrum | Robeson County | 61 |