The 925 area code covers the inland side of the East Bay in the San Francisco Bay Area. Concord, Walnut Creek, Pleasanton, Livermore and Antioch are all in it. It has no overlay.
This guide lists the cities in 925 and explains the time zone, how the code was created and how to check unknown 925 callers.
925 Area Code Quick Facts
| State | California |
| Location | Inland East Bay: Concord, Walnut Creek, Pleasanton and Livermore |
| Time zone | Pacific Time (UTC-8, UTC-7 during daylight saving time) |
| In service since | March 14, 1998 |
| Type | Geographic area code |
| Overlay | None |
| Toll-free? | No, it is a regular geographic area code |
Check any other code with our free area code lookup tool.
Where Is the 925 Area Code Located?
Area code 925 is located east of the Berkeley Hills in Northern California. It covers most of Contra Costa County and the inland part of Alameda County. Main cities:
- Concord
- Walnut Creek
- Antioch
- Pittsburg
- San Ramon
- Danville
- Pleasanton
- Livermore
- Dublin
- Brentwood
Oakland, Berkeley, Fremont and the bay shore are on the other side of the hills in 510.
What Time Zone Is the 925 Area Code In?
Concord 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. Check the clock before you dial, especially if you are several time zones away.
History of the 925 Area Code
- 1947: the Bay Area is in 415.
- 1991: the East Bay is split from 415 as 510.
- March 14, 1998: 925 is split from 510. The Berkeley Hills serve as the natural dividing line.
No overlay has been added since, so 925 is still the only code for the area. The bay shore side is covered in our 510 area code guide.
Over the Hills From Oakland
The ridge that separates 510 from 925 is a real boundary in daily life too. On the bay side are the older port and university cities. On the inland side are newer suburbs, office parks and two large national research laboratories in Livermore. The far eastern edge of 925, around Brentwood, is still partly farmland.
How to Dial a 925 Number
You need the area code for every call, even a local one.
- From the US or Canada: 1 + 925 + the seven-digit number
- From another country: your exit code + 1 + 925 + the seven-digit number
Is a Call From 925 a Scam?
A 925 number usually belongs to a household or employer in Contra Costa County or the Tri-Valley. Calls that pretend to be from a utility, a bank or a toll road agency are the ones to watch.
Watch for these warning signs:
- Threats of arrest, a lawsuit or a service shut-off unless you pay today
- Offers of a prize, a loan or a job that need a fee first
- Callers who already know part of your details and ask you to “confirm” the rest
- One-ring calls that try to make you call back
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 925 call
- Do not answer numbers you do not know.
- Never share a PIN, password or passcode with someone who called you.
- Block repeat callers and turn on your carrier spam filter.
- Report scam calls at reportfraud.ftc.gov and register at donotcall.gov.
- Forward spam texts to 7726 (SPAM).
How to Get a 925 Phone Number
Want a 925 number of your own? There are a few ways to get one.
- Carriers: any new line in the area gets a 925 number, since it is the only code there.
- VoIP and virtual number providers: search by area code, pick a 925 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 833 area code.
Area Codes Near 925
| 510, 341 | Oakland, Berkeley, Fremont |
| 415, 628 | San Francisco |
| 408, 669 | San Jose |
| 209, 350 | Stockton, Tracy, Modesto |
| 707, 369 | Vallejo, Fairfield, Napa |
Related guides: 510 area code for Oakland, 408 area code for San Jose, 916 area code for Sacramento.
925 Area Code FAQs
What city is area code 925?
Concord is the largest. Walnut Creek, Antioch, Pleasanton, Livermore and San Ramon are also in 925.
Is Oakland in 925?
No. Oakland uses 510 and 341.
Does 925 have an overlay?
No. It is the only area code for its region.
What time zone is 925?
Pacific Time.
Is 925 a toll-free number?
No. Toll-free codes are 800, 833, 844, 855, 866, 877 and 888.
Final Word
The 925 area code covers the inland East Bay on Pacific Time and has been in service since 1998. Let unknown callers leave a message and verify before you call back.
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