Area Code Atlas

CPUC approves three-way split of 619

The California Public Utilities Commission approved a two-phase, three-way split of area code 619 on June 4, 1998. The plan called for the introduction of area code 858 in the first phase and area code 935 in the second phase.

NANP-Phased three-way split of 619 (California) Numbering Plan Area (NPA) with 858 & 935 NPAs

NPA 858 split from 619

Area code 858 was introduced on June 12, 1999, as the first phase of the split of 619. The new code served northwest San Diego County, while 619 continued to serve the remaining areas.

Permissive dialing begins for 858 split

Permissive dialing for the new 858 area code began on June 12, 1999, allowing calls to be completed using either the old or new area code during the transition period.

Mandatory dialing for 858 split

Mandatory dialing for the 858 area code took effect on December 11, 1999, ending the permissive dialing period and requiring callers to use the correct area code for all calls.

NPA 619 and 858 Boundary Elimination Overlay (California)

Permissive 1+10 digit dialing for 619/858 overlay

A permissive dialing period for 1+10 digit dialing began in October 2017 for the 619 and 858 area codes, allowing customers to use either 7-digit or 1+10 digit dialing during the transition to an overlay complex.

Mandatory 1+10 digit dialing for 619/858 overlay

Mandatory 1+10 digit dialing began in April 2018 for all calls within and between the 619 and 858 area codes, coinciding with the implementation of the overlay complex.

619 and 858 overlay complex implemented

The boundary between area codes 619 and 858 was eliminated in June 2018, creating an overlay complex for all of inner San Diego County. Both area codes now serve the same geographic region, and ten-digit local dialing became mandatory at that time.

Overlay relief planned for 619 and 858

The California Public Utilities Commission approved a relief plan that eliminated the boundary between 619 and 858, creating an overlay complex for all of inner San Diego County. This change required ten-digit dialing.

Mandatory ten-digit dialing implemented for 619

Ten-digit local dialing became mandatory in June 2018 for the overlay complex of area codes 619 and 858 in San Diego County.

Mandatory ten-digit dialing implemented for 858

Ten-digit local dialing became mandatory in June 2018 for the overlay complex of area codes 619 and 858 in San Diego County.

Projected relief for San Diego area codes

According to projections, San Diego area codes 619 and 858 are not expected to require further relief until 2043.