There are 32 telephone area codes in California, as of 2015. Los Angeles is served by the 213 and 323 area codes. San Francisco has the 415 and 628 area codes, and neighboring Alameda County, which includes Oakland, is in the 510 area code.
Sacramento, the state capital, is covered by the 916 area code. The inland section of northern California, to the Nevada border, which includes Redding and Chico, is in the 530 area code, while 707 is the area code for the shore area of northern California, which includes Eureka and Santa Rosa.
The inland section of southern California, to the Nevada and Arizona borders, has the 442 and 760 area codes. It includes Blythe, Indio and Redcrest. The area code for San Bernardino is 909, and 619 serves San Diego.
San Luis Obispo is in the 805 area code, Fresno has the 559 area code, and Bakersfield's area code is 661.
The North American Numbering Plan Administration was created by AT&T in 1947. NANPA oversees the distribution of area codes in Canada, the United States and Caribbean countries. It informs the California Public Utilities Commission when it needs to add an area code, either as a separate code or to overlay an existing code. This occurs when exchanges, which means the first three numbers of a telephone number, in an existing area code are expected to be exhausted.