Area Code 357

California

Area code 357 serves California, primarily Fresno, in the Pacific Time (PT) time zone. It is an overlay area code sharing territory with area code 559.

Overlay Area Code

This area code is part of an overlay region, meaning the same geographic area is served by multiple area codes. Overlay codes were introduced to meet growing demand for phone numbers without requiring existing customers to change their numbers.

This area code shares its geographic region with: area code 559 (Fresno).

In service since: 26-Mar-2025

Learn more about overlay and split area codes →

Demographics & Economics

Total Population: 2,193,325
Population Density: 113 people/sq mi
above U.S. average (U.S.: 93 people/sq mi)
Median Household Income: $71,434
near U.S. median (U.S.: $75,144)
Poverty Rate: 18.2%
above U.S. average (U.S.: 11.5%)
Unemployment Rate: 8.9%
above U.S. average (U.S.: 3.6%)
Education Attainment: Bachelor's Degree+
19.7%
below U.S. average (U.S.: 33.7%)
High School or Lower
38.6%

Statistics are population-weighted aggregations from Census ACS 5-year estimates. Population figures are approximate — see Sources & Methodology for details on how area code populations are derived.

See how this area code compares to all US area codes in the Statistics dashboard.

Time Zone

Pacific Time (PT)

NANPA Relief Status

According to the latest NANPA analysis (July 2026), this area code is not currently listed as exhausting within the next 36 months. No relief planning is in progress for this NPA.

Source: NANPA NPA Relief Planning Reports · See all relief planning statuses

Current Time

Pacific Time (PT)

Prefix Utilization

Geographic Coverage

State

Major Cities

Fresno
Visalia
Clovis
Tulare
Madera
Porterville
Hanford
Lemoore
Sanger
Reedley
Dinuba
Selma
Corcoran
Chowchilla
Coalinga
Kerman
Parlier
Avenal
Kingsburg
Lindsay
Mendota
Farmersville
Exeter
Madera Acres

and 108 more cities

Area Code 357 geographic coverage map (light mode)

Historical Timeline of Area Code 357

Area code 357 was placed in service on March 26, 2025, as an all-services distributed overlay for area code 559 in California's central San Joaquin Valley. The overlay was authorized by the California Public Utilities Commission (CPUC) in Decision 23-12-012, issued December 14, 2023, following NANPA Application A.23-01-012 filed January 26, 2023, to address exhaustion of the 559 numbering plan area. The 13-month implementation included mandatory 10-digit dialing and a public education program with paid advertising. (Source: CPUC Decision 23-12-012)

Key milestones:

1997: The California-Nevada Code Administration (CNCA) placed area code 209 in jeopardy status due to telephone number demand exceeding forecasts, triggering special conservation measures across California NPAs. (Source: Wikipedia)
1998: Area code 559 created on November 14 via geographic split of the 209 NPA, serving the southern San Joaquin Valley including Fresno, Madera, Kings, and Tulare counties. (Source: CPUC)
2002: Telephone number pooling enforced for 209 and 559 central offices, reducing block allocations from 10,000 to 1,000 numbers per carrier assignment. (Source: Wikipedia)
2022: NANPA distributed a formal exhaustion notice for 559 on November 23. Only 59 prefixes remained as of December 20, 2022. (Source: CPUC Press Release)
2023: NANPA filed Application A.23-01-012 on January 26 requesting overlay relief. On December 14, CPUC approved the overlay in Decision 23-12-012, selecting area code 357 and adopting a 13-month implementation schedule. (Source: CPUC Decision 23-12-012)
2024: NANPA issued Planning Letter PL-624 on February 6 with implementation details. Network preparation began February 28. Permissive 1+10-digit dialing started August 26. (Source: NANPA PL-624)
2025: Mandatory 1+10-digit dialing began February 26. Area code 357 placed in service March 26 as overlay of 559. (Source: CPUC Consumer Alert)

Regulatory History

Area code 357 was authorized through a structured regulatory process managed by the California Public Utilities Commission (CPUC) and the North American Numbering Plan Administrator (NANPA). The primary authorizing document is CPUC Decision 23-12-012, issued in Application A.23-01-012. (Source: CPUC Decision 23-12-012)

Year	Event	Docket	Regulatory Action & Impact
2023	Application Filed	A.23-01-012	NANPA filed application with CPUC requesting all-services distributed overlay for 559 NPA. 559 had 59 prefixes remaining as of December 20, 2022. (Source: CPUC Press Release)
2023	Decision Issued	D.23-12-012	CPUC approved all-services distributed overlay (area code 357). Adopted 13-month implementation schedule. Required mandatory 1+10-digit dialing and paid advertising to achieve 70% customer awareness. Projected 36-year overlay lifespan. (Source: CPUC Decision 23-12-012)
2024	Planning Letter Issued	PL-624	NANPA issued implementation timeline: network prep Feb 28 2024, permissive dialing Aug 26 2024, mandatory dialing Feb 26 2025, 357 in-service Mar 26 2025. Designated test number 357-357-1357. (Source: NANPA PL-624)
2025	In-Service Date	-	Area code 357 placed in service on March 26, 2025. New telephone lines assigned 357 numbers. No existing 559 customers required to change numbers. (Source: CPUC 559/357 Area Codes Page)

County Coverage

Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 357).

County	Population	Share
Fresno, CA	1,039,739	47.4%
Tulare, CA	614,270	28.0%
Kings, CA	257,271	11.7%
Madera, CA	213,113	9.7%
Merced, CA	24,088	1.1%
Monterey, CA	18,975	0.9%
San Benito, CA	18,975	0.9%
Mariposa, CA	2,566	0.1%
Kern, CA	2,527	0.1%
Inyo, CA	1,801	0.1%