Dialing 1 a must for 510 area codes starting June 22


Residents and businesses using the 510 area code must dial 1 before dialing their phone number for all calls starting Saturday, June 22, according to the California Public Utilities Commission (CPUC).

If you don’t, your call won’t be completed and you’ll be instructed to hang up and dial again, this time adding the “1” at front.

“The dialing change paves the way for an area code overlay that will add a new 341 area code to the geographic area currently served by the 510 area code,” according to CPUC.

Those with 341 area codes will also have to dial 1 first for all calls.

The new dialing procedure will not change existing 510 phone numbers or the cost of the call. Even though you will be dialing 1 for local calls, those calls will remain local. Cost for all calls will remain unchanged.

According to CPUC, the 510 area code was created when it was split from the 415 area code in September 1991, and 510 was split again when the 925 area code was split off in 1998. The 510 area code serves the western portions of Alameda and Contra Costa counties, while the new 341 area code will serve the same geographic area currently served by the existing 510 area code.