510 Area CodeOakland, CA
Area code 510 covers Oakland and nearby communities in California, in the Pacific Time (PT) zone, home to about 1.7 million people across 33 cities. It overlays 341 and 925, so the region uses several codes and every local call needs all ten digits.
Overview
- Major City
- Oakland
- State
- California (CA)
- Timezone
- Pacific Time (PT)
- Current Time
- Overlay
- Yes – shares area with 341, 925
Overview of the 510 Area Code
What is the 510 area code?
The 510 area code serves Oakland, California, alongside other established area codes. When you see a 510 number, it indicates a local number within this geographic area.
Why was area code 510 created?
The 510 area code was introduced as an overlay to add numbers in Oakland once the existing area codes 341 and 925 began to run out of available prefixes. It added a new supply of numbers without requiring current residents to change their existing digits.
Geographic Coverage of the 510 Area Code
The 510 area code serves Oakland and surrounding areas in California. It operates within the Pacific Time (PT) time zone. It complements the coverage of area codes 341 and 925. This area code covers several key cities, including:
- Oakland
- Fremont
- Hayward
- Berkeley
- Richmond
- San Leandro
Got a call from a 510 number? It came from Oakland, CA. Since 510 overlays with 341 and 925, every local call in the region needs all ten digits to land on the right line. Inside 510, Oakland holds about 26% of the population; the rest is split across 32 smaller cities.
Oakland Area Codes Overview
Oakland is served by multiple area codes, reflecting its telecommunications needs. The 510 area code operates alongside 341, 925. Here are the area codes serving this region:
The introduction of the 510 area code helped prevent number exhaustion, ensuring a continuous supply of phone numbers across the geographic area.
What cities does area code 510 cover?
| City | State | Population | % of Area Code | % of City |
|---|---|---|---|---|
| Oakland | CA | 443,554 | 15% | 100% |
| Fremont | CA | 228,192 | 16% | 99% |
| Hayward | CA | 158,440 | 12% | 97% |
| Berkeley | CA | 121,749 | 3% | 100% |
| Richmond | CA | 115,353 | 10% | 100% |
| San Leandro | CA | 86,571 | 3% | 100% |
| Alameda | CA | 78,795 | 4% | 100% |
| Union City | CA | 66,196 | 4% | 100% |
| Castro Valley | CA | 61,388 | 3% | 100% |
| Newark | CA | 46,254 | 3% | 100% |
* Sources: Population – U.S. Census Bureau PEP, Vintage 2024 (SUB-IP-EST2024-POP). Area code assignments – NANPA CO Code data. See our data methodology.
Has area code 510 been reported for unwanted calls?
Yes – 843 unwanted-call complaints were reported to the FTC for numbers showing a 510 area code (May 29 – Jul 2, 2026).
- 55% robocalls
- ↑ 24% vs prior period
Most-reported subjects
- Other47%398
- Dropped call or no message17%144
- Calls pretending to be government, businesses, or family and friends10%84
* Caller ID is easily spoofed, so these figures reflect the number shown on caller ID, not the caller's true location – an area code alone never identifies a caller. The FTC does not verify the facts in these complaints. Source: FTC Do Not Call (DNC) Reported Calls Data, retrieved 2026-07-05.
Which prefixes and exchanges belong to area code 510?
78% assigned to a telco
- 69% Landline
- 31% Wireless
- 0% Unknown
| Prefix | Usage | Carrier |
|---|---|---|
| (510)200- | Landline | Metropcs |
| (510)201- | Landline | Peerless Network Of California |
| (510)202- | Landline | Utility Telecom Group |
| (510)203- | Wireless | T-Mobile Usa |
| (510)204- | Landline | Pacific Bell |
| (510)205- | Wireless | Sprint Spectrum |
| (510)206- | Wireless | New Cingular Wireless Pcs |
| (510)207- | Wireless | New Cingular Wireless Pcs |
| (510)208- | Landline | Pacific Bell |
| (510)209- | Wireless | Sprint Spectrum |
Frequently Asked Questions about the 510 Area Code
Who called me from a 510 number?
A 510 number is assigned to Oakland, California, so a call may come from there. But caller ID is easy to fake, and scammers often spoof a local 510 code to look nearby, so a 510 number doesn't prove the caller is local. Recently, 843 unwanted-call complaints were reported to the FTC for numbers showing the 510 code (55% flagged as robocalls). If you don't recognize the number, let it go to voicemail; a real caller will leave a message.
Is 510 a scam area code?
No area code is a scam on its own. 510 is a normal, officially assigned code for Oakland, California. Spam callers spoof local codes to raise the odds you answer, so 510 on your caller ID says nothing about who is really calling. Recently, 843 unwanted-call complaints were reported to the FTC for numbers showing the 510 code (55% flagged as robocalls). Judge the call itself, not the area code.
Why do I keep getting calls from the 510 area code?
Repeated calls from different 510 numbers are usually spoofing: a robocaller rotates through 510 numbers so each call looks local and slips past simple blocks. Recently, 843 unwanted-call complaints were reported to the FTC for numbers showing the 510 code (55% flagged as robocalls). Blocking one number rarely helps; voicemail screening, your carrier spam filter, and the Do Not Call Registry work better.
Should I answer an unknown 510 number?
If you aren't expecting a 510 call, let it ring to voicemail. Legitimate callers leave a message, most robocallers hang up when no one picks up, and answering can mark your number as active and bring more calls.
How do I block calls from the 510 area code?
Block a single 510 number from your recent-calls list (iPhone: tap the number, then Block this Caller; Android: tap the number, then Block or report spam). To cut the volume, turn on Silence Unknown Callers on iPhone or spam protection on Android, enable spam filtering from your carrier, and register at DoNotCall.gov. Blocking the entire 510 code also stops legitimate local calls, so use it only as a last resort.
Where is area code 510?
Area code 510 covers Oakland and the surrounding area in California, spanning 33 cities with about 1,674,244 residents. It shares its area with overlay codes 341, 925.
Is 510 a real area code?
Yes. 510 is an active code in the North American Numbering Plan, assigned by NANPA and in service for Oakland, California. A real code can still show up on spoofed spam calls, so treat unknown 510 calls with normal caution.
What timezone is the 510 area code in?
The 510 area code is in the Pacific Time (PT). Because a number can be kept when someone moves or switches to VoIP, a specific 510 caller may not be in that zone.
How do I call a 510 number from abroad?
From outside the US, dial your country's exit code, then 1 (the US country code), then 510 and the seven-digit number. From a mobile phone you can usually just enter +1 510 followed by the number and let the phone add the exit code for you.