Area codes 209 and 350

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.

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

Area code 209 was created in an area code split from area code 415 on October 26, 1957. On November 14, 1998, the southern half of this numbering plan area was merged into area code 559 to make more central office prefixes available.

On October 24, 2021, area code 209 was transitioned to ten-digit dialing, despite not being part of an overlay numbering plan at that time, 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 988 Suicide & Crisis Lifeline, which created a conflict for exchanges that still permitted seven-digit dialing.[1]

On November 28, 2022, the 209 numbering plan area was assigned a second area code, 350, to create an all-service overlay, in mitigation of central office prefix exhaustion from increasing code assignments in the area, which was forecast by the NANP Administrator for the fourth quarter of that year.[2] The network preparation period could be expedited since ten-digit dialing was already in effect.[3]