To address the fact that California's 559 area code is estimated to run out of new phone numbers by September 2025, the California Public Utilities Commission is adding a new 357 area code overlay.
What is an area code overlay?
An area code overlay occurs when a new area code (357) becomes available in a region already served by another area code (559).
Who's affected by this overlay?
Any person or business opening a new phone line in the 559 area will be affected by this area code overlay. Beginning in March 2025, customers will be able to choose a 357 phone number.
The area served by the 357/559 area includes parts of Fresno, Madera, Mariposa, Merced, Tulare, and Kings counties. The 559 area code serves the communities such as Clovis, Coalinga, Fresno, Madera, Porterville, Reedley, Selma, and Visalia as well as unincorporated areas.
What will be the new dialing procedure?
Effective immediately, everyone in the region needs to start dialing 10 digits — area code plus seven-digit phone number — to make calls, regardless of whether they are making local or long-distance calls.
When will the change begin?
Starting August 26, 2024, callers must dial the area code followed by the phone number on any call, even if calling locally within the same area code. Otherwise, the call will not be completed.
Beginning March 26, 2025, new telephone lines may be assigned numbers starting with the 357 area code.
What will stay the same after the overlay?
- No change: your existing telephone number, including your current area code
- No change: the cost of a call or other rates and services
- No change: local call will continue to be local calls, even when dialed with the area code.
- No change: Three digits will still connect you to 911 and 988, as well as 211, 311, 411, 511, 611, 711, or 811 (if available in your area)
Who may you contact with questions?
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