650 Area CodeSan Mateo, CA
Area code 650 covers San Mateo and nearby communities in California, in the Pacific Time (PT) zone, home to about 997,000 people across 39 cities. It's the only area code for this region, so the three digits alone place the caller.
Overview
- Major City
- San Mateo
- State
- California (CA)
- Timezone
- Pacific Time (PT)
- Current Time
- Overlay
- No – unique area code
Where is area code 650?
Area code 650 serves part of San Mateo, CA and the surrounding areas. It is a unique area code with no overlays.
Overview of the 650 Area Code
What is the 650 area code?
The 650 area code serves San Mateo, California. When you see a 650 number, it indicates a local number within this geographic area.
Why was area code 650 created?
The 650 area code was established to serve the San Mateo region in California. It provides telephone number coverage across 39 cities.
Geographic Coverage of the 650 Area Code
The 650 area code serves San Mateo and surrounding areas in California. It operates within the Pacific Time (PT) time zone. This area code covers several key cities, including:
- San Mateo
- Daly City
- Mountain View
- Redwood City
- Palo Alto
- South San Francisco
Got a call from a 650 number? It came from San Mateo, CA. No other area code overlaps the 650 territory, so the prefix alone identifies where the caller is. Inside 650, San Mateo holds about 10% of the population; the rest is split across 38 smaller cities.
San Mateo Area Code Overview
The 650 area code provides comprehensive telephone coverage for San Mateo and its surrounding communities. As the sole area code for this region, it uniquely identifies all local numbers within the service area.
What cities does area code 650 cover?
| City | State | Population | % of Area Code | % of City |
|---|---|---|---|---|
| San Mateo | CA | 103,006 | 2% | 100% |
| Daly City | CA | 101,418 | 1% | 84% |
| Mountain View | CA | 87,316 | 2% | 99% |
| Redwood City | CA | 82,982 | 4% | 100% |
| Palo Alto | CA | 67,658 | 3% | 91% |
| South San Francisco | CA | 64,660 | 4% | 100% |
| Cupertino | CA | 58,710 | 0% | 5% |
| San Bruno | CA | 42,035 | 1% | 100% |
| Pacifica | CA | 37,056 | 2% | 100% |
| Menlo Park | CA | 33,040 | 2% | 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 650 been reported for unwanted calls?
Yes – 543 unwanted-call complaints were reported to the FTC for numbers showing a 650 area code (May 29 – Jul 2, 2026).
- 50% robocalls
- ↓ 9% vs prior period
Most-reported subjects
- Other34%186
- Calls pretending to be government, businesses, or family and friends27%146
- Dropped call or no message12%65
* 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 650?
70% assigned to a telco
- 77% Landline
- 23% Wireless
- 0% Unknown
| Prefix | Usage | Carrier |
|---|---|---|
| (650)200- | Landline | Twilio International |
| (650)201- | Wireless | Sprint Spectrum |
| (650)202- | Landline | Utility Telecom Group |
| (650)203- | Landline | Bandwidth.Com Clec |
| (650)204- | Landline | Level 3 Telecom Of California |
| (650)205- | Wireless | Usa Mobility Wireless |
| (650)206- | Landline | Tpx Communications |
| (650)207- | Wireless | Verizon Wireless |
| (650)208- | Wireless | Verizon Wireless |
| (650)209- | Landline | Tpx Communications |
Frequently Asked Questions about the 650 Area Code
Who called me from a 650 number?
A 650 number is assigned to San Mateo, California, so a call may come from there. But caller ID is easy to fake, and scammers often spoof a local 650 code to look nearby, so a 650 number doesn't prove the caller is local. Recently, 543 unwanted-call complaints were reported to the FTC for numbers showing the 650 code (50% flagged as robocalls). If you don't recognize the number, let it go to voicemail; a real caller will leave a message.
Is 650 a scam area code?
No area code is a scam on its own. 650 is a normal, officially assigned code for San Mateo, California. Spam callers spoof local codes to raise the odds you answer, so 650 on your caller ID says nothing about who is really calling. Recently, 543 unwanted-call complaints were reported to the FTC for numbers showing the 650 code (50% flagged as robocalls). Judge the call itself, not the area code.
Why do I keep getting calls from the 650 area code?
Repeated calls from different 650 numbers are usually spoofing: a robocaller rotates through 650 numbers so each call looks local and slips past simple blocks. Recently, 543 unwanted-call complaints were reported to the FTC for numbers showing the 650 code (50% 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 650 number?
If you aren't expecting a 650 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 650 area code?
Block a single 650 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 650 code also stops legitimate local calls, so use it only as a last resort.
Where is area code 650?
Area code 650 covers San Mateo and the surrounding area in California, spanning 39 cities with about 997,377 residents. No other code overlays this region, so 650 alone identifies the area.
Is 650 a real area code?
Yes. 650 is an active code in the North American Numbering Plan, assigned by NANPA and in service for San Mateo, California. A real code can still show up on spoofed spam calls, so treat unknown 650 calls with normal caution.
What timezone is the 650 area code in?
The 650 area code is in the Pacific Time (PT). Because a number can be kept when someone moves or switches to VoIP, a specific 650 caller may not be in that zone.
How do I call a 650 number from abroad?
From outside the US, dial your country's exit code, then 1 (the US country code), then 650 and the seven-digit number. From a mobile phone you can usually just enter +1 650 followed by the number and let the phone add the exit code for you.