Cities in area code 820
Area code 820 serves 30 localities in California, led by Camarillo, Oxnard, Atascadero. The table lists every rate center — the billing locality each prefix is anchored to — with its share of the code's 88 active prefixes.
Camarillo, Oxnard, Atascadero, Newbury Park, Santa Barbara, Santa Maria, San Luis Obispo and Guadalupe hold the largest prefix inventories; and 21 smaller communities down to single-prefix localities. Each locality below links to its rate-center page with the full prefix list.
Metropolitan coverage: 14 rate centers belong to FCC top-100 metro areas.
Overlap note: 30 localities are shared with other area codes, so a neighbor's number may differ in its first three digits.
Clock-wise the coverage is Pacific.
A caller's real location can differ: numbers port between carriers and follow their owners when they move. Use the prefix tables to see where a specific number block was issued.
| Locality (rate center) | Active prefixes | Metro area | All codes serving it |
|---|---|---|---|
| Camarillo | 11 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Oxnard | 8 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Atascadero | 8 | — | 805, 820 |
| Newbury Park | 8 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Santa Barbara | 6 | — | 805, 820 |
| Santa Maria | 5 | — | 805, 820 |
| San Luis Obispo | 3 | — | 805, 820 |
| Guadalupe | 3 | — | 805, 820 |
| El Rio | 3 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Simi Valley | 3 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Thousand Oaks | 2 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Paso Robles | 2 | — | 805, 820 |
| Gaviota | 2 | — | 805, 820 |
| Ventura East | 2 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Arroyo Grande | 2 | — | 805, 820 |
| Lompoc | 2 | — | 805, 820 |
| Piru | 2 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Ventura Central | 2 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Santa Paula | 2 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Pismo Beach | 2 | — | 805, 820 |
| Conejo | 1 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Nipomo | 1 | — | 805, 820 |
| Los Alamos | 1 | — | 805, 820 |
| Point Mugu | 1 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Parkfield | 1 | — | 805, 820 |
| Cayucos | 1 | — | 805, 820 |
| Santa Ynez | 1 | — | 805, 820 |
| Oak View | 1 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Fillmore | 1 | Oxnard-Thousand Oaks-Ventura, CA | 805, 820 |
| Bradley | 1 | — | 805, 820 |
FAQ
What is the biggest city in area code 820?
Camarillo holds the most active prefixes (11), making it the code's largest numbering locality.
How many places does 820 cover?
30 rate centers in California hold active 820 prefixes, from Camarillo down to communities with a single prefix.
Does a 820 number guarantee the caller lives in one of these places?
No — the tables show where number blocks were issued. Porting and VoIP let people keep or acquire numbers anywhere.