The 510 area code serves the East Bay, the side of San Francisco Bay that includes Oakland and Berkeley. If a 510 number called you, this guide explains where it is, what time it is there, how the code was created and how to handle calls you do not recognize.
510 Area Code Quick Facts
| State | California |
| Location | East Bay: Oakland, Berkeley, Fremont, Hayward, Richmond |
| Time zone | Pacific Time (UTC-8, UTC-7 during daylight saving time) |
| In service since | September 2, 1991 |
| Type | Geographic area code with an overlay |
| Shares its area with | 341 |
| Toll-free? | No, it is a regular geographic area code |
Check any other code with our free area code lookup tool.
Where Is the 510 Area Code Located?
Area code 510 runs along the eastern shore of San Francisco Bay. Main cities include:
- Oakland
- Berkeley
- Fremont
- Hayward
- Richmond
- San Leandro
- Alameda
The inland side of the East Bay hills, including Concord and Walnut Creek, uses area code 925.
What Time Zone Is the 510 Area Code In?
Oakland is on Pacific Time.
- Pacific Standard Time (PST), UTC-8, in winter
- Pacific Daylight Time (PDT), UTC-7, from mid March to early November
That puts it three hours behind New York and two hours behind Chicago. A quick time check saves you from calling someone at dinner or before breakfast.
History of the 510 Area Code
The East Bay was part of area code 415 until September 2, 1991, when 510 was created. At first 510 covered both the bay shore and the inland valleys.
On March 14, 1998 the inland area was split off as 925. In July 2019, 341 was added as an overlay, so new East Bay numbers may start with either 510 or 341.
How to Dial a 510 Number
Local calls in this area are dialed with the area code included.
- From the US or Canada: 1 + 510 + the seven-digit number
- From another country: your exit code + 1 + 510 + the seven-digit number
Is a Call From 510 a Scam?
Most 510 calls are from real East Bay residents and businesses. Robocallers also spoof 510 numbers so the call looks local to people in the Bay Area.
Watch for these warning signs:
- Fake bank or card fraud alerts that ask for your PIN or passcode
- Calls about Medicare, health insurance or a car warranty you never asked about
- Messages that claim a family member is in trouble and needs money
- Pressure to stay on the line and act right now
Caller ID can be spoofed, so the number on your screen does not prove where a call comes from.
What to do with an unknown 510 call
- Hang up as soon as a call feels wrong. You do not owe a stranger an explanation.
- Verify the caller through an official number, not the one they give you.
- Block the number.
- Report scam calls at reportfraud.ftc.gov and register at donotcall.gov.
- Forward spam texts to 7726 (SPAM).
How to Get a 510 Phone Number
You do not have to live in Oakland to use a 510 number.
- Carriers: ask a carrier for an Oakland or East Bay number. You may be given 341 instead.
- VoIP and virtual number providers: search by area code, pick a 510 number and forward calls to any phone.
- Toll-free numbers: a better fit if your customers are spread across the country.
Read our guides to virtual phone numbers and the 800 area code.
Area Codes Near 510
| 341 | Same area as 510 |
| 925 | Inland East Bay: Concord, Walnut Creek, Livermore |
| 415, 628 | San Francisco and Marin County |
| 650 | The Peninsula: San Mateo, Palo Alto |
| 408, 669 | San Jose |
| 707 | Vallejo, Napa, Santa Rosa |
Related guides: 415 area code for San Francisco, 925 area code for the inland East Bay, 408 area code for San Jose.
510 Area Code FAQs
What city is area code 510?
Oakland is the largest city. Berkeley, Fremont, Hayward and Richmond also use 510.
What is the 341 area code?
341 is the overlay for the 510 area. It has been in use since 2019.
Is 510 in San Francisco?
No. 510 is across the bay from San Francisco, which uses 415 and 628.
Is 510 a toll-free number?
No. Toll-free codes are 800, 833, 844, 855, 866, 877 and 888.
Final Word
The 510 area code means Oakland and the East Bay shore. If the number is unfamiliar, let voicemail answer and check it before you call back.
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