Twin Peaks, California Area Code

Twin Peaks, CA is officially utilizing an area code overlay in which area codes 909 and 840 serve the same geographic area. Ten digit dialing (area code + seven digit number) is necessary.

In addition to Twin Peaks, CA area code information read more about area code 909 and 840 details and California area codes.

Twin Peaks, CA is located in San Bernardino County and observes the Pacific Time Zone. View our Times by Area Code tool.