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zipcodes.pro — AREA-CODE/858

858 area code

Area code 858 is in California. It covers San Diego, Chula Vista, El Cajon and 37 other places: 133 ZIP codes in San Diego County. Local time there is , Pacific Time. In service since 1999 as an overlay: it covers the same area as 619, so a number from there can have either code.

Time zone
Pacific
Largest city
San Diego
Overlays
619
In service since
1999
Rate centres
19
Prefixes assigned
562 (5,620,000 numbers)

Who calls from a 858 number

NANPA records the carrier each block of 858 numbers is assigned to. Of the 5.5 million 858 numbers assigned, 45% are with cable, internet-calling, business and other carriers (Onvoy and Level 3); 29% with mobile carriers (AT&T Mobility, T-Mobile and Verizon Wireless); 25% with local phone companies (AT&T); 1% with paging companies.

That is who the numbers were assigned to: people keep their number when they change carrier, so any one number may have moved since.

Carriers holding the most 858 numbers
CarrierKindShare
AT&TLandline24%
OnvoyCable, VoIP, other13%
AT&T MobilityMobile10%
T-MobileMobile10%
Verizon WirelessMobile9%
Level 3Cable, VoIP, other5%

An area code says where a number was issued, not where the caller is: people keep their numbers when they move, and caller ID can be set to show any number, which the FCC calls spoofing. If a call you did not expect asks for money or personal details, the FCC advises hanging up and calling the company back on a number you look up yourself. Unwanted calls can be reported to the FTC at ReportFraud.ftc.gov.

Places in area code 858

The 14 places with a telephone rate centre of their own using 858, largest first. Each links to its ZIP codes.

Places in area code 858
PlaceZIP codesPopulation
San Diego, CA 76 1,389,526
Chula Vista, CA 8 276,375
El Cajon, CA 4 104,449
La Mesa, CA 4 60,797
National City, CA 2 58,893
Poway, CA 2 48,713
La Jolla, CA 5 48,412
Coronado, CA 2 19,015
Del Mar, CA 1 3,903
Campo, CA 1 2,729
Rancho Santa Fe, CA 2 2,260
Pine Valley, CA 1 1,786
Dulzura, CA 1 749
Jacumba, CA 1 740

Nearby places using 858

These places have no rate centre of their own in NANPA's records; the nearest one uses 858. Near an area-code boundary that can be wrong for part of a town.

ZIP codes in area code 858

133 ZIP codes in 28 towns, by the town each is mailed to, largest first. Each links to its own page.

Where 858 numbers are issued

NANPA's rate centres with the most 858 prefixes (each prefix is 10,000 numbers), under NANPA's own abbreviated names.

Rate centres using area code 858
Rate centrePlacePrefixes
LA JOLLA La Jolla 166
SNDG LVTA San Diego 80
SNDG MRMS San Diego 69
DEL MAR Del Mar 45
POWAY Poway 45
RNCHOBRNDO — 41

Counties

The counties of its ZIP codes, most residents first, with how many of its ZIP codes each has.

Which code covers where you are now? What area code am I in? answers from your location.

Questions about area code 858

Where is area code 858?

Area code 858 is in California. It covers San Diego, Chula Vista, El Cajon and 37 other places: 133 ZIP codes in San Diego County.

What ZIP codes are in area code 858?

133 ZIP codes, by the town each is mailed to: San Diego (76, 92101 to 92199), Chula Vista (8, 91909 to 91921), El Cajon (4, 92019 to 92022), Spring Valley (4, 91976 to 91979) and 24 more towns. The full list is on this page.

What time zone is area code 858 in?

Pacific time.

Is a 858 number a mobile or a landline?

It can be either. 29% of 858 numbers are assigned to mobile carriers and 25% to local phone companies (NANPA, 2026-10-10); the rest are with cable, internet-calling, business and paging carriers. A number keeps its area code when it moves to another carrier.

What area codes overlay 858?

619. They cover the same area as 858, so a new number there can be given any of them.

Does a 858 number mean the caller is in California?

Not necessarily. An area code says where the number was first issued. People keep their numbers when they move or switch carriers, and calling software can show any number, so a 858 call can come from anywhere.

Other area codes in California

All 41 California area codes, by area, with the cities each covers

Source: NANPA NPA database, central office code and thousands-block assignments, 2026-10-10. Places are matched to NANPA's rate centres by name; see sources.

Cite this page

zipcodes.pro. “Area code 858.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/area-code/858

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