Barrios de Texas O
- O'Shea Keleher (2)
- Oak Forest-Garden Oaks (114)
- Oak Hills (8)
- Oak Lake (10)
- Oak Lawn (144)
- Oak Park/Northwood (19)
- Oakhurst (2)
- Oakhurst (3)
- Oaklawn (2)
- Oakwell Farms (5)
- Offatts Bayou (11)
- Old East Dallas (83)
- Old Silk Stocking Historic District (9)
- Old Town Spring (5)
- Old West Austin (13)
- Olmos Park Terrace (3)
- Onion Creek (50)
- Original Town (11)
- OST-South Union (145)
- Outer Comal (219)
- Outer East Fort Worth (62)
- Outer Mission Alton (32)
- Outer N Richland Hill/Haltom City (46)
- Outer Northwest (84)
- Outer Socorro (1)
- Outer West Dallas (26)