The Region : Area Code Change Begins

Residents of the eastern San Gabriel Valley will have a new telephone area code to contend with starting Saturday.

Diamond Bar, Pomona, Claremont, La Verne, San Dimas and Walnut, currently in the 714 area, will begin using 909. Much of western Riverside and San Bernardino counties will also make the switch.

Telephone companies will give customers nine months to adjust, according to Pacific Bell. Until Aug. 13, callers may use either 714 or 909.

Charges within and between the 909 and 714 area codes will remain the same because costs for calls are based on mileage, not area codes, Pac Bell said.

The change is necessary, officials said, because telephone companies are running out of available phone numbers because of increasing population and the growth of fax, cellular and mobile telephone services in the 714 area.