Area codes 747 and 818

Area code 818 is a California telephone area code that consists largely of the San Fernando Valley of Los Angeles, California. It was split from area code 213 on January 7, 1984.

On June 14, 1997, area code 818 was split again, with area code 626 having been created for most of the San Gabriel Valley.

Area code 747 is an overlay of 818 that became effective on May 18, 2009.

After the standardization of American telephone area codes in 1947, almost all of Los Angeles County used the 213 area code. Because the population and phone usage of the Los Angeles metropolitan area greatly increased during the 1980s and 1990s, the 213 area code was split into several new area codes, including the 818 and 310 area codes. The 818 area code entered service on January 7, 1984. Area code 626 was split from it on June 14, 1997.

In November 1999, it was proposed that "at some future date", a new 747 area code would split from 818, the new 747 serving the southern and western portions of the San Fernando Valley. This proposal sat dormant until 2007, when the telephone industry and the California Public Utilities Commission began studying implementing this 818/747 split, or possibly an overlay of all of 818 with 747. Public hearings were held, and the overall public sentiment was for an overlay rather than the split, since they could retain the 818 area code for their existing telephone numbers. The new 747 area code would be used for numbers associated with new service.

On April 24, 2008, the CPUC decided that area code 747 would overlay area code 818 effective May 18, 2009. From that date, new numbers could be assigned to the new area code. Callers within the 818 and 747 area codes would be required to dial "1" plus the area code (including calls to the same area code; cell phones could dial with or without the "1" prefix) for all calls. There was a grace period starting October 11, 2008 during which callers could still complete calls using the seven-digit number. Beginning April 18, 2009, calls would need to be dialed with "1" plus the area code and number or they would not be completed (cell phone users can omit the "1").

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