The 858 area code covers the same area as 619, including San Diego, Chula Vista and 12 more places in California.
Area code 858 is in California, on Pacific Time. In the 858 area, phone numbers are given out in San Diego County. It has been in service since June 12, 1999. 619 covers the same area, so two neighbours can have different area codes.
- Where
- San Diego County, California
- Time zone
- Pacific Time
- In service since
- June 12, 1999
- Shares its area with
- 619 (since 1982)
- Prefixes in use
- 562
- How to dial
- Local calls need 1, then the area code, then the number: 1-858-555-0142.
Find out who called you from an 858 number.
Enter the full 10-digit number to see who it is listed to and the city and state on the listing. It is the same free check as our who called me lookup. To see only the caller ID name on the number, use our free CNAM lookup. To see whether it is a mobile, a landline or a VoIP line, use our free VoIP checker. To see which carrier a (858) number is on today, use our free carrier lookup.
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San Diego holds 31% of the phone prefixes in area code 858.
A prefix is the three digits after the area code, and NANPA assigns each one to a town. Counting the 562 prefixes in use shows where 858 numbers are actually given out.
- San Diego172 prefixes, 31%
- La Jolla166 prefixes, 30%
- Poway45 prefixes, 8%
- Del Mar45 prefixes, 8%
- Chula Vista18 prefixes, 3%
- Rancho Santa Fe14 prefixes, 2%
- El Cajon14 prefixes, 2%
- La Mesa8 prefixes, 1%
Also served: Pine Valley, Campo, La Jolla and Rancho Santa Fe and 2 smaller places.
Pacific Bell (AT&T) holds the most phone number prefixes in area code 858: 151 of 562.
NANPA, which runs the North American numbering plan, assigns each prefix (the three digits after the area code) to one carrier. Here is how the 562 prefixes in use in 858 divide between carriers; holders this page does not name are grouped as other carriers.
| Carrier | Prefixes | Share |
|---|---|---|
| Pacific Bell (AT&T)AT&T's landline company | 151 | 27% |
| AT&T MobilityMobile network | 50 | 9% |
| T-MobileMobile network | 44 | 8% |
| Level 3 (Lumen)Lumen's business and wholesale network | 38 | 7% |
| Fractel | 35 | 6% |
| Teleport (AT&T)AT&T's business phone network | 26 | 5% |
| 30 other carriers | 218 | 39% |
74% of these prefixes are pooled, which means the blocks of 1,000 numbers inside them can belong to other carriers. Any number can also have been moved to another carrier since, so this shows who holds the prefixes, not who serves a given number.
Want the carrier of one exact number? Our free carrier lookup checks it, because numbers move between carriers.
Source: NANPA central office code assignments, October 1, 2026.
858 started in 1999 as an overlay on 619, and its ground has not changed since.
1999
858 starts on June 12, 1999, as an overlay on 619: new numbers on the same ground.
An 858 number on your screen can still be a scam, because caller ID is easy to fake.
- Let an unknown call go to voicemail. A real caller leaves a message; a robocaller usually does not.
- Look the number up with the box above before you call back, because calling back tells a robocaller your line is live.
- Hang up on anyone who wants gift cards, crypto or a wire transfer, or asks you to read out a code that was just texted to you.
- Report unwanted robocalls at reportfraud.ftc.gov, or paste a suspicious message into our free scam checker.
The area codes closest to 858 are 951, 949 and 714.
This list measures the distance between the centres of each area, across state lines, and shows codes that share one area together.
California has 40 other area codes.
These are the questions people ask most about area code 858.
Where is area code 858?
858 covers San Diego, Chula Vista, El Cajon and La Mesa and 10 more places in California. In the 858 area, phone numbers are given out in San Diego County.
What state is area code 858 in?
California. 858 is a California area code on Pacific Time.
What cities use area code 858?
The places holding the most 858 prefixes are San Diego, Chula Vista, El Cajon, La Mesa, National City, Coronado, Dulzura and Jacumba, out of 14 places in all. The count comes from NANPA's prefix assignments as of October 1, 2026.
Which phone company owns area code 858?
No single phone company owns 858. NANPA's records show Pacific Bell (AT&T) holds the most 858 prefixes, 151 of 562, followed by AT&T Mobility and T-Mobile. Numbers move between carriers, so check one exact number with a carrier lookup.
What time zone is area code 858 in?
858 is on Pacific Time.
When did area code 858 start?
858 went into service on June 12, 1999, as an overlay on 619: new numbers for the same area.
Is 858 the same area as 619?
Yes. 619 (since 1982) covers the same ground as 858. Nobody's number changed when it was added; new lines simply get whichever code has numbers left, so two neighbours can have different codes.
How do I dial an 858 number?
Local calls need 1, then the area code, then the number: 1-858-555-0142.
Is 858 a toll-free number?
No. 858 is a regular area code for San Diego and Chula Vista in California, not a toll-free one. The toll-free codes in North America are 800, 833, 844, 855, 866, 877 and 888.
What area codes are near 858?
The closest are 951 (Riverside, California), 949 (Irvine, California), 714/657 (Anaheim, California) and 909/840 (Ontario, California), measured between the centres of each area.
Who called me from an 858 number?
Enter the full 10-digit number in the lookup above. It returns the listed owner where there is a public record, where the number is registered, and whether it is a mobile, a landline or a VoIP line.
Is area code 858 a scam?
858 is a real California area code, so the code itself is not a warning sign. Scam callers fake local-looking numbers on purpose, so judge the call by what the caller asks for, and look the number up before calling back.
Put this lookup on your site: our free area code widget takes two lines of code and shows any US area code's state, time zone and local time.
Source: NANPA, the North American Numbering Plan Administrator: its area code database and prefix assignments, as of October 1, 2026.