Area codes 310 and 424 are telephone area codes in the North American Numbering Plan (NANP) for the U.S. state of California. The numbering plan area includes the West Los Angeles and South Bay areas of Los Angeles County, a small portion of Ventura County, and Santa Catalina Island, which is located 26 miles (42 km) south.[1]
Area code 310 was created in a split from area code 213 on November 2, 1991. On January 25, 1997, area code 310 was split, creating area code 562 for the southeast portion of Los Angeles County and a large portion of Orange County. Area code 424 was added to the remaining numbering plan area on July 26, 2006, in an overlay plan, the first in California.[2]