Callers within the 310 area code region will need to dial a “1” plus the area code and telephone number — including numbers within the local 310 area — to have their calls completed starting Wednesday, July 26th, due to an area code overlay that is taking effect.

Calls within the 310 area code that are currently dialed with seven digits will now need 11 digits. If the calls are not dialed with 11 digits, they will not be completed and a recording will instruct the caller to hang up and dial again.

In addition to changing the dialing procedure, all services, automatic dialing equipment or other types of equipment that are programmed with a seven-digit number will need to be reprogrammed with 11 digits.

The California Public Utilities Commission approved the area code overlay in August to the existing 310 area code in Southern California.

An overlay is the addition of another area code to the same geographic region as an existing area code.

The overlay does not require customers to change their existing area code.

The commission says it ordered implementation of a new 424 area code in order to ensure that consumers continue to have access to numbers from their telephone company of choice by replenishing the stock of telephone numbers available within the 310 area code region.

The 424 area code will serve customers in the same geographic region as the 310 area code, which includes the Westside and South Bay area of Los Angeles County.

New telephone lines or services may be assigned numbers with the 424 area code starting Saturday, August 26th.

Consumers who want new telephone numbers may have to accept telephone numbers with the new 424 area code.