The California Public Utilities Commission (CPUC) will begin the process to introduce a new area code to the area now served by the 510 area code, as the 510 is expected to use up its available prefixes by June 2019. The telecommunications service providers have proposed to introduce the new area code through the overlay method. Adding a new area code to the area now served by the 510 area code will provide additional prefixes and new telephone numbers for the 510 customers. The proposed overlay, pending CPUC approval, will allow all customers to keep their current phone numbers, including their area code. To avoid service disruption, the new area code will be added to the 510 area code by December 2018, six months before depletion of prefixes. In December 2018, customers requesting new phone numbers in the 510 geographic area may be assigned a new area code.
The CPUC will be holding local jurisdiction and public meetings on January 17 and February 15, 2017, to inform the local jurisdictions and the public, and to hear concerns about adding a new area code to the 510 area code. More information is available at http://www.cpuc.ca.gov/510areacode.