Area code 858, Telephone prefix in San Diego County, California, US.
Area code 858 serves northern San Diego County and covers communities from La Jolla to Poway and Rancho Bernardo. The prefix follows North American phone numbering format with three digits followed by seven digits for each local line.
The area code 858 was established in 1999 as an overlay to area code 619 to meet growing demand for phone numbers in the region. This addition became necessary as population and business growth expanded across northern San Diego County.
The area code covers regions with major educational institutions, including the University of California San Diego, contributing to the technological development of the region.
When calling within this area, you dial the three-digit prefix along with the seven-digit local number. Modern phone services handle this numbering format automatically without requiring any special knowledge or configuration from users.
The region is home to headquarters of major technology and energy companies including Qualcomm and Sempra Energy. These corporate centers operate within communities covered by this prefix and significantly shape the local economy.
The community of curious travelers
AroundUs brings together thousands of curated places, local tips, and hidden gems, enriched daily by 60,000 contributors worldwide.
