| District of California area codes: 858 | |
|---|---|
| Country | United States |
| State/Province | California |
| Major City | San Diego |
| Time Zone | Pacific |
| Prefix | County | Primary City | Company |
|---|---|---|---|
| 858-900 | San Diego | San Diego, CA | Cf Communications DBA Telekenex |
| 858-901 | San Diego | San Diego, CA | Xo California |
| 858-905 | San Diego | San Diego, CA | Mci Worldcom Communications, Ca |
| 858-909 | San Diego | La Jolla, CA | Pacific Bell |
| 858-914 | San Diego | Rancho Santa Fe, CA | Level 3 Communications |
| 858-922 | San Diego | San Diego, CA | Cellco Partnership DBA Verizon Wireless |
| 858-923 | San Diego | Rancho Santa Fe, CA | Pac - West Telecomm |
| 858-924 | San Diego | Rancho Bernardo, CA | Pacific Bell |
| 858-925 | San Diego | San Diego, CA | O1 Communications |
| 858-926 | San Diego | San Diego, CA | O1 Communications |
| 858-927 | San Diego | Rancho Bernardo, CA | O1 Communications |
| 858-935 | San Diego | San Diego, CA | Xo California |
| 858-939 | San Diego | San Diego, CA | Pacific Bell |
| 858-942 | San Diego | San Diego, CA | Teleport Communications America |
| 858-943 | San Diego | San Diego, CA | Tw Telecom Of California Lp |
| 858-945 | San Diego | San Diego, CA | Cellco Partnership DBA Verizon Wireless |
| 858-946 | San Diego | San Diego, CA | Xo California |
| 858-947 | San Diego | Del Mar, CA | Pac - West Telecomm |
| 858-949 | San Diego | San Diego, CA | American Messaging (am) |
| 858-951 | San Diego | Rancho Santa Fe, CA | Global Crossing Local Services-ca |
There are 389 prefixes, In the code area, the major cities are Poway, CA. The major city is San Diego.