Area codes 209 and 350

Numbering plan areas in California (blue) and border states. Area code 209 is shown in red.

Area codes 209 and 350 are telephone area codes in the North American Numbering Plan (NANP) for the U.S. state of California. Their service area includes Stockton, Modesto, Turlock, Merced, Winton, Atwater, Livingston, Manteca, Ripon, Tracy, Lodi, Galt, Sonora, Los Banos, San Andreas, Mariposa, and Yosemite, the northern San Joaquin Valley (part of the Central Valley), and the Sierra Foothills.

The area code 209 was created in an area code split from area code 415 on October 26, 1957.

The southern half of the original numbering plan area was split off and integrated into area code 559 on November 14, 1998.

On October 24, 2021, area code 209 was transitioned to ten-digit dialing (1+10 digits for landlines), despite not being part of an overlay numbering plan at that time, in which multiple area codes are assigned to a numbering plan area. The area code had telephone numbers assigned for the central office code 988. In 2020, 988 was designated nationwide as a dialing code for the National Suicide Prevention Lifeline, which created a conflict for exchanges that still permitted seven-digit dialing.^[1]

The area code 209 will be overlaid by new area code 350, which CPUC approved as an all-service overlay, on November 28, 2022, as central office prefixes of area code 209 were exhausted by the fourth quarter that year.^[2] That was expedited since ten- (or eleven)-digit dialing was already in effect. ^[3]