820 Area CodeOxnard, CA
Area code 820 covers Oxnard and nearby communities in California, in the Pacific Time (PT) zone, home to about 1,556,801 people across 79 cities. It was added in 2018 as an overlay of 805, so the same region uses both codes and every local call needs all ten digits.
Overview
- Major City
- Oxnard
- State
- California (CA)
- Timezone
- Pacific Time (PT)
- Current Time
- –:––
- Overlay
- Yes – shares area with 805
Where is area code 820?
Area code 820 serves part of Oxnard, CA and the surrounding areas. It has a single overlay (805) that serves the same area.
Overview of the 820 Area Code
What is the 820 area code?
The 820 area code serves Oxnard, California, alongside other established area codes. When you see a 820 number, it indicates a local number within this geographic area.
Why was area code 820 created?
Area code 820 went into service on June 30, 2018, as an overlay of 805. An overlay adds a second code to the same territory instead of splitting it: existing 805 numbers kept their digits, new lines began receiving 820 numbers, and local calls in the region require all ten digits.
Geographic Coverage of the 820 Area Code
The 820 area code serves Oxnard and surrounding areas in California. It operates within the Pacific Time (PT) time zone. It complements the coverage of area code 805. This area code covers several key cities, including:
- Oxnard
- Simi Valley
- Thousand Oaks
- Santa Maria
- San Buenaventura (Ventura)
- Santa Barbara
Got a call from an 820 number? It came from Oxnard, CA. Since 820 overlays with 805, every local call in the region needs all ten digits to land on the right line. Of the listed cities' population, Oxnard accounts for about 14.3%; the rest is split across 78 smaller cities.
Oxnard Area Codes Overview
Oxnard is served by multiple area codes, reflecting its telecommunications needs. The 820 area code operates alongside 805. Here are the area codes serving this region:
The introduction of the 820 area code helped prevent number exhaustion, ensuring a continuous supply of phone numbers across the geographic area.
What cities does area code 820 cover?
| City | State | Population | Population in 820 | % of listed-city population | % of City |
|---|---|---|---|---|---|
| Oxnard | CA | 200,616 | 200,616 | 14.3% | 100.0% |
| Simi Valley | CA | 125,778 | 125,778 | 8.9% | 100.0% |
| Thousand Oaks | CA | 124,229 | 124,229 | 8.8% | 100.0% |
| Santa Maria | CA | 111,346 | 111,346 | 7.9% | 100.0% |
| San Buenaventura (Ventura) | CA | 109,831 | 109,831 | 7.8% | 100.0% |
| Santa Barbara | CA | 87,291 | 87,291 | 6.2% | 100.0% |
| Camarillo | CA | 69,881 | 69,881 | 5.0% | 100.0% |
| San Luis Obispo | CA | 49,729 | 49,729 | 3.5% | 100.0% |
| Lompoc | CA | 43,594 | 43,594 | 3.1% | 100.0% |
| Moorpark | CA | 35,621 | 35,621 | 2.5% | 100.0% |
| Goleta | CA | 32,611 | 32,611 | 2.3% | 100.0% |
| Santa Paula | CA | 31,786 | 31,786 | 2.3% | 100.0% |
| El Paso de Robles (Paso Robles) | CA | 31,568 | 31,568 | 2.3% | 100.0% |
| Atascadero | CA | 29,743 | 29,743 | 2.1% | 100.0% |
| Orcutt | CA | 28,905 | 28,905 | 2.1% | 100.0% |
| Isla Vista | CA | 23,096 | 23,096 | 1.6% | 100.0% |
| Port Hueneme | CA | 21,325 | 21,325 | 1.5% | 100.0% |
| Arroyo Grande | CA | 18,249 | 18,249 | 1.3% | 100.0% |
| Fillmore | CA | 17,216 | 17,216 | 1.2% | 100.0% |
| Nipomo | CA | 16,714 | 16,714 | 1.2% | 100.0% |
| Los Osos | CA | 14,276 | 14,276 | 1.0% | 100.0% |
| Carpinteria | CA | 12,876 | 12,876 | 0.9% | 100.0% |
| Grover Beach | CA | 12,534 | 12,534 | 0.9% | 100.0% |
| Morro Bay | CA | 10,591 | 10,591 | 0.8% | 100.0% |
| Montecito | CA | 8,965 | 8,965 | 0.6% | 100.0% |
| Guadalupe | CA | 8,735 | 8,735 | 0.6% | 100.0% |
| Pismo Beach | CA | 7,984 | 7,984 | 0.6% | 100.0% |
| Templeton | CA | 7,674 | 7,674 | 0.6% | 100.0% |
| Ojai | CA | 7,563 | 7,563 | 0.5% | 100.0% |
| Oceano | CA | 7,286 | 7,286 | 0.5% | 100.0% |
| El Rio | CA | 7,198 | 7,198 | 0.5% | 100.0% |
| Mira Monte | CA | 6,854 | 6,854 | 0.5% | 100.0% |
| Vandenberg Village | CA | 6,497 | 6,497 | 0.5% | 100.0% |
| Cambria | CA | 6,032 | 6,032 | 0.4% | 100.0% |
| Solvang | CA | 5,988 | 5,988 | 0.4% | 100.0% |
| Buellton | CA | 5,023 | 5,023 | 0.4% | 100.0% |
| Santa Ynez | CA | 4,418 | 4,418 | 0.3% | 100.0% |
| Oak View | CA | 4,066 | 4,066 | 0.3% | 100.0% |
| Mission Hills | CA | 3,576 | 3,576 | 0.3% | 100.0% |
| Meiners Oaks | CA | 3,571 | 3,571 | 0.3% | 100.0% |
| Vandenberg AFB | CA | 3,338 | 3,338 | 0.2% | 100.0% |
| Santa Rosa Valley | CA | 3,334 | 3,334 | 0.2% | 100.0% |
| Casa Conejo | CA | 3,249 | 3,249 | 0.2% | 100.0% |
| Channel Islands Beach | CA | 3,103 | 3,103 | 0.2% | 100.0% |
| Cayucos | CA | 2,592 | 2,592 | 0.2% | 100.0% |
| Lake Nacimiento | CA | 2,411 | 2,411 | 0.2% | 100.0% |
| Mission Canyon | CA | 2,381 | 2,381 | 0.2% | 100.0% |
| San Miguel | CA | 2,336 | 2,336 | 0.2% | 100.0% |
| Piru | CA | 2,063 | 2,063 | 0.2% | 100.0% |
| Los Alamos | CA | 1,890 | 1,890 | 0.1% | 100.0% |
| Avilla Beach | CA | 1,627 | 1,627 | 0.1% | 100.0% |
| Lake Sherwood | CA | 1,527 | 1,527 | 0.1% | 100.0% |
| Toro Canyon | CA | 1,508 | 1,508 | 0.1% | 100.0% |
| Los Ranchos | CA | 1,477 | 1,477 | 0.1% | 100.0% |
| Summerland | CA | 1,448 | 1,448 | 0.1% | 100.0% |
| Shandon | CA | 1,295 | 1,295 | 0.1% | 100.0% |
| Callender | CA | 1,262 | 1,262 | 0.1% | 100.0% |
| Santa Margarita | CA | 1,259 | 1,259 | 0.1% | 100.0% |
| Los Olivos | CA | 1,132 | 1,132 | 0.1% | 100.0% |
| Santa Susana | CA | 1,037 | 1,037 | 0.1% | 100.0% |
| Saticoy | CA | 1,029 | 1,029 | 0.1% | 100.0% |
| Blacklake | CA | 930 | 930 | 0.1% | 100.0% |
| Los Berros | CA | 641 | 641 | 0.1% | 100.0% |
| Woodlands | CA | 576 | 576 | 0.0% | 100.0% |
| San Ardo | CA | 517 | 0 | 0.0% | 0.0% |
| New Cuyama | CA | 517 | 0 | 0.0% | 0.0% |
| Ballard | CA | 467 | 467 | 0.0% | 100.0% |
| San Simeon | CA | 462 | 462 | 0.0% | 100.0% |
| Garden Farms | CA | 386 | 386 | 0.0% | 100.0% |
| Lockwood | CA | 379 | 0 | 0.0% | 0.0% |
| Oak Shores | CA | 337 | 337 | 0.0% | 100.0% |
| Whitley Gardens | CA | 285 | 285 | 0.0% | 100.0% |
| Edna | CA | 193 | 193 | 0.0% | 100.0% |
| Sisquoc | CA | 183 | 183 | 0.0% | 100.0% |
| Casmalia | CA | 138 | 138 | 0.0% | 100.0% |
| Creston | CA | 94 | 94 | 0.0% | 100.0% |
| Bradley | CA | 93 | 93 | 0.0% | 100.0% |
| Garey | CA | 68 | 68 | 0.0% | 100.0% |
| Cuyama | CA | 57 | 0 | 0.0% | 0.0% |
City population is shown in full. The share of each city inside 820 is measured from Census tract centroids, not estimated from a rate-center match – so a city split between two codes appears on both, at the fraction each one actually holds. The “% of listed-city population” column uses the full populations of the cities listed here.
What counties does area code 820 cover?
1,556,801 residents across 3 counties, counted inside the 820 boundary — a county split between codes contributes only its part.
Sources: City populations – U.S. Census Bureau PEP, Vintage 2024 (SUB-IP-EST2024-POP). State populations – the same program, Vintage 2025 (CO-EST2025-ALLDATA). Area-code footprint and county populations – 2020 Census Centers of Population, mapped against NANP area code boundaries. The share of each city inside a code is measured the same way, against Census place boundaries from the Census Bureau's TIGERweb service. Area code assignments – NANPA CO Code data. See our data methodology.
Has area code 820 been reported for unwanted calls?
Yes – 145 unwanted-call complaints were reported to the FTC for numbers showing a 820 area code (May 29 – Aug 14, 2026).
- 55% robocalls
- ↑ 23% vs prior period
Most-reported subjects
- Other46%66
- Calls pretending to be government, businesses, or family and friends21%31
- Reducing your debt (credit cards, mortgage, student loans)18%26
Caller ID is easily spoofed, so these figures reflect the number shown on caller ID, not the caller's true location – an area code alone never identifies a caller. The FTC does not verify the facts in these complaints. Source: FTC Do Not Call (DNC) Reported Calls Data, retrieved 2026-08-17.
Which prefixes and exchanges belong to area code 820?
5% assigned to a telco
- 86% Landline
- 14% Wireless
- 0% Unknown
of 51 | ||
| Prefix | Usage | Carrier |
|---|---|---|
| (820)200- | Landline | Advanced Telecom Solutions |
| (820)201- | Landline | Shelcomm |
| (820)202- | Wireless | Csc Wireless |
| (820)203- | Wireless | T-Mobile Usa |
| (820)204- | Wireless | New Cingular Wireless Pcs |
| (820)205- | Wireless | New Cingular Wireless Pcs |
| (820)206- | Wireless | T-Mobile Usa |
| (820)207- | Wireless | New Cingular Wireless Pcs |
| (820)208- | Landline | Tpx Communications |
| (820)209- | Landline | Bandwidth.Com Clec |
| (820)212- | Wireless | New Cingular Wireless Pcs |
| (820)222- | Landline | Fractel |
| (820)234- | Landline | Fractel |
| (820)280- | Landline | Hd Carrier |
| (820)288- | Landline | Fractel |
| (820)299- | Landline | Fractel |
| (820)300- | Landline | Onvoy |
| (820)333- | Landline | Fractel |
| (820)336- | Landline | Fractel |
| (820)345- | Landline | Fractel |
| (820)346- | Landline | Fractel |
| (820)348- | Landline | Fractel |
| (820)356- | Landline | Fractel |
| (820)380- | Landline | Onvoy |
| (820)386- | Landline | Fractel |
| (820)400- | Landline | Twilio International |
| (820)426- | Landline | Ton80 Communications |
| (820)432- | Landline | Fractel |
| (820)444- | Landline | Fractel |
| (820)465- | Landline | Fractel |
| (820)500- | Landline | Fractel |
| (820)529- | Landline | Fractel |
| (820)587- | Landline | Fractel |
| (820)600- | Landline | Fractel |
| (820)666- | Landline | Fractel |
| (820)667- | Landline | Fractel |
| (820)732- | Landline | Fractel |
| (820)758- | Landline | Fractel |
| (820)777- | Landline | Fractel |
| (820)786- | Landline | Fractel |
| (820)799- | Landline | Fractel |
| (820)800- | Landline | Fractel |
| (820)822- | Landline | Fractel |
| (820)823- | Landline | Onvoy |
| (820)837- | Landline | Ton80 Communications |
| (820)842- | Landline | Fractel |
| (820)888- | Landline | Terra Nova Telecom |
| (820)899- | Landline | Fractel |
| (820)900- | Landline | Fractel |
| (820)946- | Landline | Fractel |
| (820)999- | Landline | Fractel |
| No prefixes match “”. | ||
Frequently Asked Questions about the 820 Area Code
Who called me from a 820 number?
A 820 number is assigned to Oxnard, California, so a call may come from there. But caller ID is easy to fake, and scammers often spoof a local 820 code to look nearby, so a 820 number doesn't prove the caller is local. Recently, 145 unwanted-call complaints were reported to the FTC for numbers showing the 820 code (55% flagged as robocalls). If you don't recognize the number, let it go to voicemail; a real caller will leave a message.
Is 820 a scam area code?
No area code is a scam on its own. 820 is a normal, officially assigned code for Oxnard, California. Spam callers spoof local codes to raise the odds you answer, so 820 on your caller ID says nothing about who is really calling. Recently, 145 unwanted-call complaints were reported to the FTC for numbers showing the 820 code (55% flagged as robocalls). Judge the call itself, not the area code.
Why do I keep getting calls from the 820 area code?
Repeated calls from different 820 numbers are usually spoofing: a robocaller rotates through 820 numbers so each call looks local and slips past simple blocks. Recently, 145 unwanted-call complaints were reported to the FTC for numbers showing the 820 code (55% flagged as robocalls). Blocking one number rarely helps; voicemail screening, your carrier spam filter, and the Do Not Call Registry work better.
Should I answer an unknown 820 number?
If you aren't expecting a 820 call, let it ring to voicemail. Legitimate callers leave a message, most robocallers hang up when no one picks up, and answering can mark your number as active and bring more calls.
How do I block calls from the 820 area code?
Block a single 820 number from your recent-calls list (iPhone: tap the number, then Block this Caller; Android: tap the number, then Block or report spam). To cut the volume, turn on Silence Unknown Callers on iPhone or spam protection on Android, enable spam filtering from your carrier, and register at DoNotCall.gov. Blocking the entire 820 code also stops legitimate local calls, so use it only as a last resort.
Where is area code 820?
Area code 820 covers Oxnard and the surrounding area in California, spanning 79 cities with about 1,556,801 residents. It shares its area with overlay code 805.
When did area code 820 go into service?
Area code 820 went into service on June 30, 2018. It was added as an overlay of 805, so 820 numbers serve the same area that 805 already covered.
Is 820 a real area code?
Yes. 820 is an active code in the North American Numbering Plan, assigned by NANPA and in service for Oxnard, California. A real code can still show up on spoofed spam calls, so treat unknown 820 calls with normal caution.
What timezone is the 820 area code in?
The 820 area code is in the Pacific Time (PT). Because a number can be kept when someone moves or switches to VoIP, a specific 820 caller may not be in that zone.
How do I call a 820 number from abroad?
From outside the US, dial your country's exit code, then 1 (the US country code), then 820 and the seven-digit number. From a mobile phone you can usually just enter +1 820 followed by the number and let the phone add the exit code for you.