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zipcodes.pro — AREA-CODE/650

650 area code

Area code 650 is in California. It covers San Mateo, Mountain View, Redwood City and 30 other places: 44 ZIP codes in San Mateo and Santa Clara counties. Local time there is , Pacific Time. In service since 1997, with no overlay.

Time zone
Pacific
Largest city
San Mateo
Overlays
none
In service since
1997
Rate centres
15
Prefixes assigned
716 (7,160,000 numbers)

Who calls from a 650 number

NANPA records the carrier each block of 650 numbers is assigned to. Of the 7.1 million 650 numbers assigned, 41% are with cable, internet-calling, business and other carriers (Onvoy and Level 3); 32% with local phone companies (AT&T); 26% 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 650 numbers
CarrierKindShare
AT&TLandline31%
OnvoyCable, VoIP, other13%
AT&T MobilityMobile10%
T-MobileMobile10%
Level 3Cable, VoIP, other6%
Verizon WirelessMobile6%

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 650

The 13 places with a telephone rate centre of their own using 650, largest first. Each links to its ZIP codes.

Places in area code 650
PlaceZIP codesPopulation
San Mateo, CA 5 103,105
Mountain View, CA 6 83,732
Redwood City, CA 5 82,447
Palo Alto, CA 6 67,237
South San Francisco, CA 2 64,305
Pacifica, CA 1 37,261
Los Altos, CA 3 30,698
Millbrae, CA 1 22,689
Half Moon Bay, CA 1 11,391
Woodside, CA — 5,126
Moss Beach, CA 1 2,683
La Honda, CA 1 1,269
Pescadero, CA 1 691

Nearby places using 650

These places have no rate centre of their own in NANPA's records; the nearest one uses 650. Near an area-code boundary that can be wrong for part of a town.

ZIP codes in area code 650

44 ZIP codes in 22 towns, by the town each is mailed to, largest first. Each links to its own page.

Where 650 numbers are issued

NANPA's rate centres with the most 650 prefixes (each prefix is 10,000 numbers), under NANPA's own abbreviated names.

Rate centres using area code 650
Rate centrePlacePrefixes
PALO ALTO Palo Alto 145
SAN MATEO San Mateo 126
MT VIEW Mountain View 93
SSNFRNCSCO South San Francisco 89
REDWOOD CY Redwood City 65
SNCRL-BLMT — 44

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 650

Where is area code 650?

Area code 650 is in California. It covers San Mateo, Mountain View, Redwood City and 30 other places: 44 ZIP codes in San Mateo and Santa Clara counties.

What ZIP codes are in area code 650?

44 ZIP codes, by the town each is mailed to: San Mateo (5, 94401 to 94497), Mountain View (6, 94035 to 94043), Redwood City (5, 94061 to 94065), Palo Alto (6, 94301 to 94309) and 18 more towns. The full list is on this page.

What time zone is area code 650 in?

Pacific time.

Is a 650 number a mobile or a landline?

It can be either. 26% of 650 numbers are assigned to mobile carriers and 32% 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.

Does a 650 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 650 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 650.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/area-code/650

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