Oakland, CA Area Codes

Area codes serving Oakland

Oakland sits in California, part of the West region and the Pacific Time zone. Its numbers are spread across an overlay of 2 codes that all cover the same ground: 341, 510.

The original code is 510 (in service since 1991). As the area ran low on numbers, regulators added overlay codes on top instead of splitting the city, so longtime residents kept their numbers while new lines received a newer code.

Code	Area served	In service
341	Western Alameda and Contra Costa counties on the East Bay, including Oakland and Fremont	July 22, 2019
510	Western Alameda and Contra Costa counties on the East Bay, including Oakland and Fremont	September 2, 1991

Nearby cities sharing these area codes

• Fremont
• Hayward
• Berkeley
• Richmond
• San Leandro
• Alameda
• Union City
• Newark
• San Pablo
• El Cerrito
• Emeryville
• Albany
• Hercules

How to pick an area code for a new number

When you activate a new line in Oakland, the carrier assigns whichever code has numbers available — you usually can't choose. If a specific code matters to you (for example the prestige of 510), ask the carrier whether any blocks remain, or request a number transfer. All codes here dial identically and cost the same.

Dialing in Oakland

Because Oakland is an overlay area, 10-digit dialing is mandatory: always dial the area code plus the seven-digit number, even for a neighbor. See 10-digit dialing and overlay area codes for the background. For every code in California, visit the California area codes page.