Barrios de Pennsylvania O
- Oak Lane-East Oak Lane (11)
- Oakwood (1)
- Old City (75)
- Old Uptown Harrisburg (9)
- Olde Kensington (67)
- Olney (23)
- Orchard Park (7)
- Outer Kenhorst/Shillington (2)
- Outer Lancaster (47)
- Outer Wilkes-Barre (5)
- Outer York/Valley View/Grantley (11)
- Outlying South Allegheny (17)
- Overbrook (5)
- Overbrook (64)
- Oxford Circle-Castor (17)