820 Area CodeOxnard, CA
Area code 820 covers Oxnard and nearby communities in California, in the Pacific Time (PT) zone, home to about 1.4 million people across 79 cities. It overlays 802, so the same region uses both 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 802
Where is area code 820?
Area code 820 serves part of Oxnard, CA and the surrounding areas. It has a single overlay (802) 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?
The 820 area code was introduced as an overlay to add numbers in Oxnard once the existing area code 802 began to run out of available prefixes. It added a new supply of numbers without requiring current residents to change their existing 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 802. 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 802, every local call in the region needs all ten digits to land on the right line. Inside 820, Oxnard holds about 14% of the population; 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 802. 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 | % of Area Code | % of City |
|---|---|---|---|---|
| Oxnard | CA | 200,616 | 0% | 100% |
| Simi Valley | CA | 125,778 | 0% | 99% |
| Thousand Oaks | CA | 124,229 | 1% | 95% |
| Santa Maria | CA | 111,346 | 0% | 100% |
| San Buenaventura (Ventura) | CA | 109,831 | 0% | 100% |
| Santa Barbara | CA | 87,291 | 0% | 100% |
| Camarillo | CA | 69,881 | 0% | 100% |
| San Luis Obispo | CA | 49,729 | 0% | 100% |
| Lompoc | CA | 43,594 | 0% | 100% |
| Moorpark | CA | 35,621 | 0% | 100% |
* Sources: Population – U.S. Census Bureau PEP, Vintage 2024 (SUB-IP-EST2024-POP). Area code assignments – NANPA CO Code data. See our data methodology.
Has area code 820 been reported for unwanted calls?
Yes – 61 unwanted-call complaints were reported to the FTC for numbers showing a 820 area code (May 29 – Jul 2, 2026).
- 44% robocalls
- ↓ 26% vs prior period
Most-reported subjects
- Other49%30
- Calls pretending to be government, businesses, or family and friends16%10
- Reducing your debt (credit cards, mortgage, student loans)15%9
* 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 2026-07-05.
Which prefixes and exchanges belong to area code 820?
5% assigned to a telco
- 86% Landline
- 14% Wireless
- 0% Unknown
| 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 |
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, 61 unwanted-call complaints were reported to the FTC for numbers showing the 820 code (44% 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, 61 unwanted-call complaints were reported to the FTC for numbers showing the 820 code (44% 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, 61 unwanted-call complaints were reported to the FTC for numbers showing the 820 code (44% 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 1,408,457 residents. It shares its area with overlay code 802.
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.