Postal reference / United States
94027Atherton, California
ZIP code 94027 is a United States postal code for Atherton, California. Its county association is San Mateo County. The map reference point is at 37.4563, -122.2002.
- State / territory
- California
- Recorded place name
- Atherton
- County association
- San Mateo
- Estimated coordinate
- 37.4563, -122.2002
View on OpenStreetMap - ZIP prefix
- 940 · 45 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.
Area
- Land area
- 5.027 sq mi (2023 Census Gazetteer)
Figures are for the ZIP Code Tabulation Area (ZCTA) that most closely matches this ZIP code, not an exact match to USPS delivery boundaries. Source: U.S. Census Bureau, 2023 Gazetteer + 2023 ACS 5-Year Estimates, retrieved 2026-09-27. How to read this data.
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California directoryNearby ZIP code reference points
| ZIP code | Place | State | County association | Miles |
|---|---|---|---|---|
| 94025 | Menlo Park | CA | San Mateo | 1.4 |
| 94061 | Redwood City | CA | San Mateo | 1.8 |
| 94063 | Redwood City | CA | San Mateo | 1.8 |
| 94304 | Palo Alto | CA | Santa Clara | 1.8 |
| 94301 | Palo Alto | CA | Santa Clara | 2.9 |
| 94305 | Stanford | CA | Santa Clara | 3.1 |
| 94302 | Palo Alto | CA | Santa Clara | 3.3 |
| 94309 | Palo Alto | CA | Santa Clara | 3.3 |
Straight-line distance between reference points. Nearby points do not prove that ZIP areas touch.
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