Barrios de Washington O
- Oakbrook (2)
- Ogden (8)
- Old Evergreen Highway (1)
- Olde Town (1)
- Olympic West (1)
- Olympus (1)
- Opportunity (6)
- Orchards (3)
- Orchards Area (30)
- Outer Bremerton (22)
- Outer Longview (3)
- Outer Mercer Island (12)
- Outer Silverdale (18)
- Outlying Issaquah (7)
- Outlying Lynnwood-Snohomish (41)
- Outlying McChord (13)
- Outlying Newcastle (6)
- Outlying Puyallup (24)
- Outlying Vancouver (32)
- Overlake (56)