Area Code 837

California

Area code 837 serves California, primarily Chico, in the Pacific Time (PT) time zone. It is an overlay area code sharing territory with area code 530.

Published: February 17, 2026Verified against NANPA and FCC records

Overlay Area Code

This area code shares its geographic footprint with an overlay code, so the same cities are served by two area codes. Because overlays leave existing numbers untouched, this region's relief planning favors adding codes over redrawing boundaries.

The codes serving this same region: area code 530 (Chico).

In service since: 31-Jan-2025

Learn more about overlay and split area codes →

Demographics & Economics

Total Population: 1,632,822
Population Density: 36 people/sq mi
below U.S. average (U.S.: 95 people/sq mi)
Median Household Income: $76,373
near U.S. median (U.S.: $80,734)
Poverty Rate: 13.7%
near U.S. average (U.S.: 12.5%)
Unemployment Rate: 6.5%
above U.S. average (U.S.: 5.2%)
Education Attainment: Bachelor's Degree+
30.1%
below U.S. average (U.S.: 35.7%)
High School or Lower
28.6%

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 income ranking and density ranking.

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

Chico
Redding
Davis
Woodland
West Sacramento
El Dorado Hills
Linda
South Lake Tahoe
Oroville
Olivehurst
Cameron Park
Truckee
Live Oak
Alpine
Susanville
Red Bluff
Grass Valley
North Auburn
Auburn
Marysville
Diamond Springs
Anderson
Placerville
Shasta Lake

and 280 more cities

Area Code 837 geographic coverage map (light mode)

Demographics

The estimated population served by area code 837 is approximately 1,632,822. The population density is 36 people per square mile, which is lower than the national average of 95. The median household income is $76,373, which is near the national median of $80,734. Approximately 30.1% of adults hold a bachelor's degree or higher, compared to the national rate of 35.7%. This rate is lower than the national average. The poverty rate stands at 13.7%, which is near the national rate of 12.5%.

History

Area code 837 serves as an overlay for the same territory as area code 530. It was introduced in 2025 to provide additional phone number capacity for the region. It shares its territory with area code area code 530.

County Coverage

Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 837).

County	Population	Share
Butte, CA	245,837	15.1%
Shasta, CA	193,637	11.9%
El Dorado, CA	163,765	10.0%
Yolo, CA	162,881	10.0%
Tehama, CA	127,243	7.8%
Nevada, CA	118,974	7.3%
Yuba, CA	115,564	7.1%
Sutter, CA	115,336	7.1%
Placer, CA	104,868	6.4%
Solano, CA	89,026	5.5%
Siskiyou, CA	46,132	2.8%
Lassen, CA	34,309	2.1%
Glenn, CA	30,076	1.8%
Colusa, CA	24,074	1.5%
Plumas, CA	22,408	1.4%
Trinity, CA	14,804	0.9%
Modoc, CA	11,700	0.7%
Humboldt, CA	4,280	0.3%
Sierra, CA	4,077	0.2%
Alpine, CA	1,679	0.1%
Mono, CA	1,423	0.1%
Amador, CA	406	0.0%
Lake, OR	323	0.0%