Postal reference / United States
91023Mount Wilson, California
ZIP code 91023 is a United States postal code for Mount Wilson, California. Its county association is Los Angeles County. The map reference point is at 34.2264, -118.0662.
- State / territory
- California
- Recorded place name
- Mount Wilson
- County association
- Los Angeles
- Estimated coordinate
- 34.2264, -118.0662
View on OpenStreetMap - ZIP prefix
- 910 · 25 ZIP codes share it
- Data source
- GeoNames postal reference, snapshot September 26, 2026
GeoNames reference data. County associations may not include every intersecting county, place names are postal names rather than legal boundaries, and coordinates are approximate. This is not address validation.
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California directoryNearby ZIP code reference points
| ZIP code | Place | State | County association | Miles |
|---|---|---|---|---|
| 91024 | Sierra Madre | CA | Los Angeles | 4.3 |
| 91003 | Altadena | CA | Los Angeles | 4.5 |
| 91025 | Sierra Madre | CA | Los Angeles | 4.5 |
| 91001 | Altadena | CA | Los Angeles | 4.8 |
| 91104 | Pasadena | CA | Los Angeles | 5.3 |
| 91107 | Pasadena | CA | Los Angeles | 5.4 |
| 91066 | Arcadia | CA | Los Angeles | 6.2 |
| 91077 | Arcadia | CA | Los Angeles | 6.2 |
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