Area Code 831

California

Area code 831 serves California, primarily Salinas, in the Pacific Time (PT) time zone. It was created from a split of area code 408.

Split Area Code

This area code was created by splitting an existing area code into separate geographic regions. When a split occurs, some customers in the original area code region are assigned the new area code.

This area code was split from area code 408 (San Jose).

In service since: 11-Jul-1998

Learn more about overlay and split area codes →

Demographics & Economics

Total Population: 1,004,963
Population Density: 163 people/sq mi
above U.S. average (U.S.: 93 people/sq mi)
Median Household Income: $94,486
above U.S. median (U.S.: $75,144)
Poverty Rate: 11.0%
near U.S. average (U.S.: 11.5%)
Unemployment Rate: 5.2%
above U.S. average (U.S.: 3.6%)
Education Attainment: Bachelor's Degree+
35.6%
near U.S. average (U.S.: 33.7%)
High School or Lower
31.0%

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

Salinas
Santa Cruz
Watsonville
Hollister
Seaside
Monterey
Soledad
Marina
Greenfield
Prunedale
Live Oak
Pacific Grove
Scotts Valley
Soquel
Capitola
Rio del Mar
Gonzales
Interlaken
Castroville
Ben Lomond
Aptos
Pleasure Point
Boulder Creek
Felton

and 39 more cities

Area Code 831 geographic coverage map (light mode)

Demographics

The estimated population served by area code 831 is approximately 1,004,963. The population density is 163 people per square mile, which is higher than the national average of 93. The median household income is $94,486, which is higher than the national median of $75,144. Approximately 35.6% of adults hold a bachelor's degree or higher, compared to the national rate of 33.7%. This rate is near the national average. The poverty rate stands at 11.0%, which is near the national rate of 11.5%.

History

Area code 831 was created from a split of area code 408. It was introduced in 1998 as part of a geographic division to provide additional numbering resources.