Magic Number in Riverside County: 951

The area code in western Riverside County changes to 951 on Saturday, splitting away from the old 909 that now belongs exclusively to western San Bernardino County and slivers of Los Angeles County.

People calling Riverside, Corona and other communities with the new area code will hear a recorded message if they dial 909.

They’ll be told of the change and will have to redial the number with the correct area code, said Steven Smith, spokesman for SBC California.

The California Public Utilities Commission voted in November to create the new area code to deal with a shortage of phone numbers.

The area code change actually began in July, but SBC California gave customers a three-month grace period to become accustomed to the change. During that time, callers who dialed 909 were still put through.

“We’re not expecting any type of disruption,” Smith said. “This is something we’ve been working on with communities for quite some time now.”

Cities keeping the 909 area code include Ontario, San Bernardino, Rancho Cucamonga, Big Bear and Claremont.

Cellphone numbers also are affected by the switch, depending on where the accounts are based. Customers should call their cellphone service providers for more information.

The 760 area code in the eastern portions of Riverside and San Bernardino counties remains in use. A complete list of affected prefixes is available at www.sbc.com/areacodes.