Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — AREA-CODE/341

341 area code

Area code 341 is in California. It covers Oakland, Hayward, Richmond and 18 other places: 55 ZIP codes in Alameda and Contra Costa counties. Local time there is , Pacific Time. In service since 2019 as an overlay: it covers the same area as 510, so a number from there can have either code.

Time zone
Pacific
Largest city
Oakland
Overlays
510
In service since
2019
Rate centres
13
Prefixes assigned
113 (1,130,000 numbers)

Who calls from a 341 number

NANPA records the carrier each block of 341 numbers is assigned to. Of the 1.1 million 341 numbers assigned, 64% are with cable, internet-calling, business and other carriers (Onvoy, Bandwidth and Fractel); 36% with mobile carriers (AT&T Mobility, T-Mobile and Verizon Wireless).

That is who the numbers were assigned to: people keep their number when they change carrier, so any one number may have moved since.

Carriers holding the most 341 numbers
CarrierKindShare
OnvoyCable, VoIP, other37%
AT&T MobilityMobile13%
T-MobileMobile13%
Verizon WirelessMobile9%
BandwidthCable, VoIP, other8%
FractelCable, VoIP, other5%

An area code says where a number was issued, not where the caller is: people keep their numbers when they move, and caller ID can be set to show any number, which the FCC calls spoofing. If a call you did not expect asks for money or personal details, the FCC advises hanging up and calling the company back on a number you look up yourself. Unwanted calls can be reported to the FTC at ReportFraud.ftc.gov.

Places in area code 341

The 4 places with a telephone rate centre of their own using 341, largest first. Each links to its ZIP codes.

Places in area code 341
PlaceZIP codesPopulation
Oakland, CA 26 439,418
Hayward, CA 7 158,801
Richmond, CA 7 115,505
Crockett, CA 1 3,372

Nearby places using 341

These places have no rate centre of their own in NANPA's records; the nearest one uses 341. Near an area-code boundary that can be wrong for part of a town.

ZIP codes in area code 341

55 ZIP codes in 13 towns, by the town each is mailed to, largest first. Each links to its own page.

Where 341 numbers are issued

NANPA's rate centres with the most 341 prefixes (each prefix is 10,000 numbers), under NANPA's own abbreviated names.

Rate centres using area code 341
Rate centrePlacePrefixes
FRNK MAIN — 16
HAYWARD Hayward 13
OKLD BKLY Oakland 12
OKLD FRTVL Oakland 10
RICHMOND Richmond 10
ELSBR-PINL — 9

Counties

The counties of its ZIP codes, most residents first, with how many of its ZIP codes each has.

Which code covers where you are now? What area code am I in? answers from your location.

Questions about area code 341

Where is area code 341?

Area code 341 is in California. It covers Oakland, Hayward, Richmond and 18 other places: 55 ZIP codes in Alameda and Contra Costa counties.

What ZIP codes are in area code 341?

55 ZIP codes, by the town each is mailed to: Oakland (26, 94601 to 94666), Hayward (7, 94540 to 94557), Richmond (7, 94801 to 94850), San Leandro (3, 94577 to 94579) and 9 more towns. The full list is on this page.

What time zone is area code 341 in?

Pacific time.

Is a 341 number a mobile or a landline?

It can be either. 36% of 341 numbers are assigned to mobile carriers and 0% to local phone companies (NANPA, 2026-10-10); the rest are with cable, internet-calling, business and paging carriers. A number keeps its area code when it moves to another carrier.

What area codes overlay 341?

510. They cover the same area as 341, so a new number there can be given any of them.

Does a 341 number mean the caller is in California?

Not necessarily. An area code says where the number was first issued. People keep their numbers when they move or switch carriers, and calling software can show any number, so a 341 call can come from anywhere.

Other area codes in California

All 41 California area codes, by area, with the cities each covers

Source: NANPA NPA database, central office code and thousands-block assignments, 2026-10-10. Places are matched to NANPA's rate centres by name; see sources.

Cite this page

zipcodes.pro. “Area code 341.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/area-code/341

Underlying data is public domain or openly licensed — sources, vintages and licences.