| District of California area codes: 925 | |
|---|---|
| Country | United States |
| State/Province | California |
| Major City | Oakland |
| Time Zone | Pacific |
| Prefix | County | Primary City | Company |
|---|---|---|---|
| 925-608 | Contra Costa | Martinez, CA | Broadwing Communications |
| 925-609 | Contra Costa | Concord, CA | Pacific Bell |
| 925-621 | Alameda | Pleasanton, CA | U.s. Telepacific Corp. |
| 925-623 | Alameda | Pleasanton, CA | Sprint Spectrum L.p. |
| 925-625 | Contra Costa | Oakley, CA | Pacific Bell |
| 925-626 | Contra Costa | Brentwood, CA | Mcimetro Access Transmission Services LLC |
| 925-627 | Contra Costa | Walnut Creek, CA | U.s. Telepacific Corp. |
| 925-628 | Contra Costa | Antioch, CA | Cellco Partnership DBA Verizon Wireless |
| 925-631 | Contra Costa | Moraga, CA | Pacific Bell |
| 925-634 | Contra Costa | Brentwood, CA | Pacific Bell |
| 925-635 | Contra Costa | Pittsburg, CA | Teleport Communications Group - San Francisco |
| 925-639 | Contra Costa | Walnut Creek, CA | T-mobile Usa |
| 925-640 | Contra Costa | San Ramon, CA | New Cingular Wireless PCS |
| 925-642 | Contra Costa | Antioch, CA | New Cingular Wireless PCS |
| 925-643 | Contra Costa | Pittsburg, CA | U.s. Telepacific Corp. |
| 925-646 | Contra Costa | Concord, CA | Pacific Bell |
| 925-648 | Contra Costa | Danville, CA | Pacific Bell |
| 925-658 | Contra Costa | Walnut Creek, CA | Teleport Communications Group - San Francisco |
| 925-659 | Contra Costa | San Ramon, CA | Teleport Communications Group - San Francisco |
| 925-660 | Alameda | Pleasanton, CA | Tw Telecom Of California Lp |
There are 552 prefixes, In the code area, the major cities are Antioch, CA;Bay Point, CA;Brentwood, CA;Concord, C. The major city is Oakland.