Find the last 4 digits (ZIP+4) for an address in 91023

ZIP 91023, Mount Wilson, CA is filled in. Just type the street address.

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ZIP Code 91023 – Mount Wilson, CA

Mount Wilson, California · Los Angeles County · Pacific time

ZIP code91023
CityMount Wilson
StateCalifornia
CountyLos Angeles County
PopulationNot published (no Census ZIP area)
Time zonePacific · local time
ZIP typePO box or unique ZIP (no Census area)
Center (lat, long)34.2264, -118.0662

Area codes in this area

626

These are the area codes that most often serve ZIP 91023 (including overlays). The exact area code depends on the phone number — landlines, mobiles and overlays can differ even on the same street.

Map

Nearby ZIP codes

91024 Sierra Madre · 3.7 mi91003 Altadena · 4.5 mi91025 Sierra Madre · 4.5 mi91001 Altadena · 4.7 mi91107 Pasadena · 4.8 mi91104 Pasadena · 5.3 mi91066 Arcadia · 6.2 mi91077 Arcadia · 6.2 mi

About ZIP 91023

ZIP code 91023 is assigned to Mount Wilson, California. It lies in Los Angeles County. It is a PO-box-only or single-address ZIP, so the Census Bureau does not publish an area for it; the location shown is approximate. The closest neighboring ZIP is 91024 (Sierra Madre), about 3.7 miles away.

Every address in 91023 also has a 4-digit add-on code (ZIP+4) that points to a smaller delivery area. Use the box above to find it.

Sources: US Census Bureau (ZCTA, county relationship files), GeoNames (CC BY 4.0), NANPA via NumberResearch.org (CC BY 4.0). Map © OpenStreetMap contributors. ZIP areas are approximate. Population: U.S. Census Bureau, ACS 5-year estimates, 2024 (ZCTA). Data sources