Postal reference / United States
91788Walnut, California
ZIP code 91788 is a United States postal code for Walnut, California. Its county association is Los Angeles County. The map reference point is at 34.0203, -117.8653.
- State / territory
- California
- Recorded place name
- Walnut
- County association
- Los Angeles
- Estimated coordinate
- 34.0203, -117.8653
View on OpenStreetMap - ZIP prefix
- 917 · 64 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 directoryOther ZIP codes in Walnut, CA
Walnut has 2 ZIP codes in the reference dataset.
- 91789Los Angeles
Nearby ZIP code reference points
| ZIP code | Place | State | County association | Miles |
|---|---|---|---|---|
| 91789 | Walnut | CA | Los Angeles | 0.6 |
| 91792 | West Covina | CA | Los Angeles | 1.9 |
| 91748 | Rowland Heights | CA | Los Angeles | 3.2 |
| 91765 | Diamond Bar | CA | Los Angeles | 3.3 |
| 91791 | West Covina | CA | Los Angeles | 3.6 |
| 91744 | La Puente | CA | Los Angeles | 4.2 |
| 91723 | Covina | CA | Los Angeles | 4.7 |
| 91747 | La Puente | CA | Los Angeles | 4.8 |
Straight-line distance between reference points. Nearby points do not prove that ZIP areas touch.
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