The first area code overlay in California was implemented by the CPUC and the telecommunications industry on July 26, 2006. The CPUC approved an area code overlay for the 310 region to accommodate the need for additional telephone numbers prefixes. The new 424 area code serves customers in the same geographic region as the current 310 area code, which includes the Westside and South Bay area of Los Angeles County and a small portion of Ventura County (see our map). With the area code overlay, people with a 310 or 424 area code must dial 1 + area code + seven-digit number when making calls.
On December 31, 2005, customers began dialing 1 + area code + seven-digit number whenever a call is placed from the 310 area code. On July 26, 2006, customers were required to use the new dialing procedure for all calls.
The local calling area or the cost of long distance calls for 310 customers has not changed as a result of implementing the 424 code. Three digits will continue to be all that is necessary to reach 911, as well as 211, 311, 411, 511, 611, and 711. For the associated documents related to the 310 area code overlay, check out the links to the left.