Area Code 858
California
Area code 858 serves California, primarily San Diego, in the Pacific Time (PT) time zone. It is an overlay area code sharing territory with area code 619.
Overlay Area Code
This area code is part of an overlay region, meaning the same geographic area is served by multiple area codes. Overlay codes were introduced to meet growing demand for phone numbers without requiring existing customers to change their numbers.
This area code shares its geographic region with: area code 619 (San Diego).
In service since: 12-Jun-1999
Geographic Coverage
Area code 858 serves California, primarily the San Diego area, in the Pacific Time (PT). It covers 36 communities. The geographic center of this area code is approximately 32.80°N, 116.91°W.
History
Area code 858 serves as an overlay for the same territory as area code 619. It was introduced in 1999 to provide additional phone number capacity for the region. It shares its territory with area code area code 619.
Demographics
The estimated population served by area code 858 is approximately 2,371,073. The population density is 780 people per square mile, which is higher than the national average of 94. The median household income is $102,285, which is higher than the national median of $78,538. Approximately 42.1% of adults hold a bachelor's degree or higher, compared to the national rate of 35.0%. This rate is higher than the national average. The poverty rate stands at 10.4%, which is lower than the national rate of 12.4%.
Demographics & Economics
- Total Population
- 2,371,073
- Population Density
- 780 people/sq miabove U.S. average (U.S.: 94 people/sq mi)
- Median Household Income
- $102,285above U.S. median (U.S.: $78,538)
- Poverty Rate
- 10.4%below U.S. average (U.S.: 12.4%)
- Unemployment Rate
- 6.2%above U.S. average (U.S.: 5.2%)
- Education Attainment
- Bachelor's Degree+42.1%above U.S. average (U.S.: 35.0%)High School or Lower23.9%
Statistics are population-weighted aggregations from Census ACS 5-year estimates.See Sources for details.
Geographic Coverage
State
CA
Major Cities
- San Diego
- Chula Vista
- El Cajon
- Encinitas
- La Mesa
- Santee
- Poway
- La Presa
- Lemon Grove
- Imperial Beach
- Rancho San Diego
- Winter Gardens
- Casa de Oro-Mount Helix
- Coronado
- Bostonia
- Alpine
- Bonita
- Solana Beach
- Jamul
- Eucalyptus Hills
- Harbison Canyon
- Del Mar
- Granite Hills
- Crest
and 12 more cities
Time Zone
- Pacific Time (PT)
Current Time
County Coverage
Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 858).
| County | Population | Share |
|---|---|---|
| San Diego, CA | 2,371,073 | 100.0% |
Call Context
This area code serves the same metropolitan region as area code 619, including San Diego, in California. It was introduced as an overlay of area code 619, meaning both codes serve the same geographic territory.
Nearby Area Codes
Area codes geographically closest to 858.
Other Area Codes in California
Area codes that also serve California, linked for easy comparison.
Frequently Asked Questions
Common questions about area code 858 and how phone numbering works.
Phone numbers are assigned based on where the number was originally provisioned, not the caller's current location. Mobile phones retain their number when users move, and businesses may use numbers from regions where they don't have a physical presence. VoIP services can also provision numbers from virtually any area code.
Yes, mobile phones can have numbers from any area code in the region they were activated. Wireless carriers assign numbers from available pools regardless of phone type. When users change carriers or move to new areas, they typically keep their original number, which may have a different area code than their current location.
Start by looking up the area code on this site to understand its general geographic region. For the specific number, options include using your carrier's caller ID features or checking public directories. If you suspect fraud, you can report it to the FTC. To file a complaint about robocalls or spoofed numbers, visit the FCC Consumer Complaint Center. You can also register your number with the National Do Not Call Registry to reduce unwanted calls. Keep in mind that caller ID can display any name the caller chooses to set.
When an area's pool of available phone numbers runs low, regulators may introduce an "overlay" area code that covers the same geographic territory as the original. Both codes coexist, and new numbers are assigned from whichever code has availability. This area code shares its region with area code 619, area code 619. Learn more in our overlay vs split guide.
While San Diego is a prominent city in this area code's coverage, the code serves the broader surrounding region as well. Area codes are assigned geographically and typically cover multiple cities, towns, and communities beyond any single anchor city.
The estimated total population served by area code 858 is based on aggregated U.S. Census Bureau data for the counties within this area code. The population varies significantly between dense urban codes serving millions and rural codes covering smaller populations. You can find the specific population figure in the demographics section above.