805
Covers central California
In service since 1957
Split from area code 213
Overlay with 820
City facts
Thousand Oaks area codes
Area codes for central California: history, overlays and how to dial.
805820
Thousand Oaks uses area codes 805 and 820. Because more than one area code serves the same area, local calls need all ten digits.
About these area codes
820
Covers central California
In service since 2018
Overlay with 805
How to call a number in Thousand Oaks
Inside the US
1 (805) 555-0123Dial 1, the area code, then the seven-digit number.Local call
(805) 555-0123Overlay area: always include the area code.From outside the US
+1 805 555 0123Use your country's exit code or +, then 1 for the US.Thousand Oaks is on Pacific Time (PT); check the time before calling from another zone.
Other cities that share these codes
Nearby area codes
| Area code | Used in | Distance |
|---|---|---|
| 310 | Beverly Hills | 28 mi |
| 424 | Beverly Hills | 28 mi |
| 323 | Beverly Hills | 28 mi |
| 213 | West Hollywood | 30 mi |
| 626 | Alhambra | 43 mi |
| 562 | Downey | 46 mi |
| 661 | Palmdale | 51 mi |
| 909 | West Covina | 54 mi |
Thousand Oaks quick facts
Thousand Oaks was incorporated on October 7, 1964.
Incorporated1964October 7, 1964
CountyVentura CountyCalifornia
Area codes805, 820Population125,676Census ACS estimateZIP codes491320, 91360, 91361…Elevation886 ft270 m
Time zonePacific TimePT
Dates, namesake and elevation from Wikipedia: Thousand Oaks, California and Wikidata (checked 2026-11-08); population and ZIP codes from the U.S. Census Bureau.
Questions
What area code is Thousand Oaks?
Thousand Oaks uses area codes 805 and 820. Because more than one area code serves the same area, local calls need all ten digits.
When did area code 805 start?
Area code 805 dates from 1957, when it was split from area code 213.
When did area code 820 start?
Area code 820 dates from 2018.
Do I need to dial the area code for local calls in Thousand Oaks?
Yes. 805 and 820 share the same area as an overlay, so every local call needs the area code plus the seven-digit number (ten digits).
What time zone is area code 805 in?
Thousand Oaks is on Pacific Time (PT).
What other cities use area code 805?
Other cities in this network that share 805 and 820 include Simi Valley, Oxnard, Santa Maria, San Luis Obispo, Paso Robles.
Sources: Area codes 805 and 820, Area codes 805 and 820 (Wikipedia) and Wikidata, checked 2026-11-08. Numbering plans change; the North American Numbering Plan Administrator is the official record.