| O'Dear Creek | rises in NW McDowell County and flows E on the N side of Pompey Ridge into Threemile Creek. |
| O'Neals Township | N Johnston County. |
| Oak City | town in NW Martin County. Site given the name Goose Nest by a Union soldier on a raid. Inc. as Conoho, 1891. Name changed to Oak City, 1905, because of confusion with Conetoe; name selected from a calendar advertising Oak City Laundry in Raleigh. |
| Oak Forest | community in E Iredell County. Settled prior to 1800. Store there operated by James Gay. Thriving business community around 1900. |
| Oak Grove | community in SW Brunswick County. |
| Oak Grove | community in central Davie County between Elisha and Dutchmans Creeks. Est. prior to 1879. Also known as Maine. |
| Oak Grove | community on Little Lick Creek in E Durham County. |
| Oak Grove | community in S Jones County. |
| Oak Grove | community in N Macon County between Caler Cove Branch and Lakey Creek. |
| Oak Grove | community in NW Northampton County. The post office there, 1907-26, was known as Stancell. |