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
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 94. The median household income is $94,486, which is higher than the national median of $78,538. Approximately 35.6% of adults hold a bachelor's degree or higher, compared to the national rate of 35.0%. This rate is near the national average. The poverty rate stands at 11.0%, which is lower than the national rate of 12.4%.
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.
Geographic Coverage
Area code 831 serves California, primarily the Salinas area, in the Pacific Time (PT). It covers 63 communities. The geographic center of this area code is approximately 36.78°N, 121.75°W.
Demographics & Economics
- Total Population
- 1,004,963
- Population Density
- 163 people/sq miabove U.S. average (U.S.: 94 people/sq mi)
- Median Household Income
- $94,486above U.S. median (U.S.: $78,538)
- Poverty Rate
- 11.0%below U.S. average (U.S.: 12.4%)
- Unemployment Rate
- 5.2%near U.S. average (U.S.: 5.2%)
- Education Attainment
- Bachelor's Degree+35.6%near U.S. average (U.S.: 35.0%)High School or Lower31.0%
Statistics are population-weighted aggregations from Census ACS 5-year estimates.See Sources for details.
Geographic Coverage
State
CA
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
Time Zone
- Pacific Time (PT)
Current Time
County Coverage
Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 831).
| County | Population | Share |
|---|---|---|
| Monterey, CA | 506,457 | 50.4% |
| Santa Cruz, CA | 272,769 | 27.1% |
| Santa Clara, CA | 140,783 | 14.0% |
| San Benito, CA | 84,954 | 8.5% |
Call Context
This area code covers multiple cities and communities across a broad region in California. It was created as a geographic split from area code 408, dividing the original territory into separate numbering regions.
Nearby Area Codes
Area codes geographically closest to 831.
Other Area Codes in California
Area codes that also serve California, linked for easy comparison.
Frequently Asked Questions
Common questions about area code 831 and how phone numbering works.
Phone numbers are assigned based on where the number was originally provisioned, not the caller's current location. Mobile phones retain their number when users move, and businesses may use numbers from regions where they don't have a physical presence. VoIP services can also provision numbers from virtually any area code.
Yes, mobile phones can have numbers from any area code in the region they were activated. Wireless carriers assign numbers from available pools regardless of phone type. When users change carriers or move to new areas, they typically keep their original number, which may have a different area code than their current location.
Start by looking up the area code on this site to understand its general geographic region. For the specific number, options include using your carrier's caller ID features or checking public directories. If you suspect fraud, you can report it to the FTC. To file a complaint about robocalls or spoofed numbers, visit the FCC Consumer Complaint Center. You can also register your number with the National Do Not Call Registry to reduce unwanted calls. Keep in mind that caller ID can display any name the caller chooses to set.
Area codes are sometimes "split" when an existing code runs out of available number combinations. In a split, the original territory is divided geographically, with each portion receiving its own area code. This area code was split from area code 408. See our guide on splits and overlays for details.
While Salinas is a prominent city in this area code's coverage, the code serves the broader surrounding region as well. Area codes are assigned geographically and typically cover multiple cities, towns, and communities beyond any single anchor city.
The estimated total population served by area code 831 is based on aggregated U.S. Census Bureau data for the counties within this area code. The population varies significantly between dense urban codes serving millions and rural codes covering smaller populations. You can find the specific population figure in the demographics section above.