Missouri Neighborhoods O
- O'Fallon St Charles (51)
- Oak Meyer Gardens (3)
- Oak Park Northwest (7)
- Oak Park Southeast (8)
- Oak Park Southwest (9)
- Oak Tree Farm (2)
- Oaks Ridge Meadows (1)
- Oakville (7)
- Old Westport (7)
- Oldham Farms (4)
- Ott-Chrisman (7)
- Outer North Springfield (39)
- Outer Southeast Springfield (45)
- Outer Southwest Springfield (96)