831 area code
Area code 831 is in California. It covers Salinas, Santa Cruz, Watsonville and 61 other places: 57 ZIP codes in Monterey, Santa Cruz and San Benito counties. Local time there is , Pacific Time. In service since 1998, with no overlay.
- State
- California
- Time zone
- Pacific
- Largest city
- Salinas
- Overlays
- none
- In service since
- 1998
- Rate centres
- 24
- Prefixes assigned
- 406 (4,060,000 numbers)
Who calls from a 831 number
NANPA records the carrier each block of 831 numbers is assigned to. Of the 3.8 million 831 numbers assigned, 41% are with cable, internet-calling, business and other carriers (Onvoy and Bandwidth); 32% with mobile carriers (AT&T Mobility, T-Mobile and Verizon Wireless); 27% with local phone companies (AT&T).
That is who the numbers were assigned to: people keep their number when they change carrier, so any one number may have moved since.
| Carrier | Kind | Share |
|---|---|---|
| AT&T | Landline | 26% |
| Onvoy | Cable, VoIP, other | 16% |
| AT&T Mobility | Mobile | 11% |
| T-Mobile | Mobile | 11% |
| Verizon Wireless | Mobile | 10% |
| Bandwidth | Cable, VoIP, other | 5% |
An area code says where a number was issued, not where the caller is: people keep their numbers when they move, and caller ID can be set to show any number, which the FCC calls spoofing. If a call you did not expect asks for money or personal details, the FCC advises hanging up and calling the company back on a number you look up yourself. Unwanted calls can be reported to the FTC at ReportFraud.ftc.gov.
Places in area code 831
The 22 places with a telephone rate centre of their own using 831, largest first. Each links to its ZIP codes.
| Place | ZIP codes | Population |
|---|---|---|
| Salinas, CA | 8 | 161,761 |
| Santa Cruz, CA | 6 | 61,607 |
| Watsonville, CA | 2 | 51,712 |
| Hollister, CA | 2 | 43,811 |
| Monterey, CA | 4 | 29,613 |
| Soledad, CA | 1 | 26,365 |
| Greenfield, CA | 1 | 20,232 |
| King City, CA | 1 | 13,604 |
| Carmel, CA | 2 | 12,565 |
| Gonzales, CA | 1 | 8,492 |
| Ben Lomond, CA | 1 | 6,858 |
| Castroville, CA | 1 | 6,720 |
| Aptos, CA | 2 | 6,404 |
| Carmel Valley, CA | 1 | 6,316 |
| Boulder Creek, CA | 1 | 4,632 |
| Felton, CA | 1 | 4,093 |
| San Juan Bautista, CA | 1 | 2,033 |
| Big Sur, CA | 1 | 1,464 |
| Tres Pinos, CA | 1 | 901 |
| Chualar, CA | 1 | 812 |
| San Ardo, CA | 1 | 462 |
| San Lucas, CA | 1 | 134 |
Nearby places using 831
These places have no rate centre of their own in NANPA's records; the nearest one uses 831. Near an area-code boundary that can be wrong for part of a town.
- Seaside
- Marina
- Live Oak
- Pacific Grove
- Scotts Valley
- Soquel
- Capitola
- Rio del Mar
- Interlaken
- Pleasure Point
- Twin Lakes
- Carmel Valley Village
- Del Monte Forest
- Pebble Beach
- Day Valley
- Ridgemark
- Las Lomas
- Seacliff
- Freedom
- Carmel By The Sea
- Bonny Doon
- Pajaro
- Amesti
- Pine Canyon
- La Selva Beach
- Aptos Hills-Larkin Valley
- Corralitos
- Elkhorn
- Del Rey Oaks
- Brookdale
- Boronda
- Jolon
- Fort Hunter Liggett
- Mount Hermon
- Pasatiempo
- Paradise Park
- Sand City
- Davenport
- Zayante
- Spreckels
- Pajaro Dunes
- Moss Landing
ZIP codes in area code 831
57 ZIP codes in 37 towns, by the town each is mailed to, largest first. Each links to its own page.
Where 831 numbers are issued
NANPA's rate centres with the most 831 prefixes (each prefix is 10,000 numbers), under NANPA's own abbreviated names.
| Rate centre | Place | Prefixes |
|---|---|---|
SALINAS | Salinas | 84 |
SANTA CRUZ | Santa Cruz | 76 |
MONTEREY | Monterey | 64 |
WATSONVL | Watsonville | 30 |
HOLLISTER | Hollister | 22 |
APTOS | Aptos | 19 |
Counties
The counties of its ZIP codes, most residents first, with how many of its ZIP codes each has.
Which code covers where you are now? What area code am I in? answers from your location.
Questions about area code 831
Where is area code 831?
Area code 831 is in California. It covers Salinas, Santa Cruz, Watsonville and 61 other places: 57 ZIP codes in Monterey, Santa Cruz and San Benito counties.
What ZIP codes are in area code 831?
57 ZIP codes, by the town each is mailed to: Salinas (8, 93901 to 93915), Santa Cruz (6, 95060 to 95065), Watsonville (2, 95076 to 95077), Hollister (2, 95023 to 95024) and 33 more towns. The full list is on this page.
What time zone is area code 831 in?
Pacific time.
Is a 831 number a mobile or a landline?
It can be either. 32% of 831 numbers are assigned to mobile carriers and 27% to local phone companies (NANPA, 2026-10-10); the rest are with cable, internet-calling, business and paging carriers. A number keeps its area code when it moves to another carrier.
Does a 831 number mean the caller is in California?
Not necessarily. An area code says where the number was first issued. People keep their numbers when they move or switch carriers, and calling software can show any number, so a 831 call can come from anywhere.
Other area codes in California
- 209 Fresno
- 213 Los Angeles
- 279 Sacramento
- 310 Torrance
- 323 Los Angeles
- 341 Oakland
- 350 Stockton
- 357 Fresno
- 369 Santa Rosa
- 408 San Jose
- 415 San Francisco
- 424 Torrance
- 442 Oceanside
- 510 Oakland
- 530 Chico
- 559 Fresno
- 562 Long Beach
- 619 San Diego
- 626 Pasadena
- 628 San Francisco
- 650 San Mateo
- 657 Anaheim
- 661 Bakersfield
- 669 San Jose
- 707 Santa Rosa
- 714 Anaheim
- 738 Los Angeles
- 747 Glendale
- 760 Oceanside
- 805 Bakersfield
- 818 Glendale
- 820 Oxnard
- 837 Chico
- 840 Fontana
- 858 San Diego
- 909 Fontana
- 916 Sacramento
- 925 Concord
- 949 Irvine
- 951 Riverside
All 41 California area codes, by area, with the cities each covers
Source: NANPA NPA database, central office code and thousands-block assignments, 2026-10-10. Places are matched to NANPA's rate centres by name; see sources.
Cite this page
zipcodes.pro. “Area code 831.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/area-code/831
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