California Area Codes Click on an area code to go to the page for that code. The area codes in red are 442 and 760. All blue areas are California area codes. Area code 760 is a California telephone area code that was split from area code 619 on March 22, 1997.Area code 442 is an overlay of 760 that became effective on November 21, 2009.ll blue areas are California area codes. Area code 760 is a California telephone area code that was split from area code 619 on March 22, 1997. Area code 442 is an overlay of 760 that became effective on November 21, 2009.