628 Area Code — San Francisco, CA
Area code 628 serves San Francisco and 1 other city in California. Local time follows America/Los_Angeles. It overlays with 415, so 10-digit dialling is required.
- State
- California
- Primary city
- San Francisco
- Timezone
- America/Los_Angeles
- In service since
- 2015
- Type
- Overlay
- Overlay codes
- 415
Overlay of 415
Cities Served by 628
The 628 area code covers 2 cities and communities in California.
- San Francisco
- San Mateo
About Area Code 628
Area code 628 is a North American Numbering Plan (NANP) area code that has been in service since 2015. It is administered by NANPA on behalf of the FCC and serves the California region anchored on San Francisco.
628 is an overlay code, which means it shares its geographic boundaries with one or more existing area codes (415). Overlays are created when a region exhausts the supply of phone numbers in its original area code. Within an overlay region, residents must dial all 10 digits even for local calls, because the same 7-digit number can exist under multiple area codes.
Mobile numbers in 628 are portable: a person who moved away from San Francisco may still carry a 628 mobile number on their device. If you receive an unexpected call from a 628 number, run it through the reverse lookup tool above for the most accurate, free identification.
If you live or do business in California, you may also interact with neighbouring or overlay codes (415). See the related codes section below to explore the rest of California.
Other California Area Codes
Continue exploring the California numbering plan.
628 Area Code FAQ
Where is area code 628?
Area code 628 is located in California, primarily serving San Francisco and surrounding cities including San Mateo. The region operates on PT (America/Los_Angeles) time.
What state is 628 area code?
628 is a California area code. It was put into service in 2015 as an overlay and shares its geographic footprint with overlay code 415.
Is 628 a scam area code?
628 is a legitimate North American area code allocated by NANPA to California. Like any geographic area code, scammers sometimes spoof 628 numbers — judge each call by content (urgent demands, unfamiliar transfers) rather than the area code alone. Run the specific number through our reverse lookup if you're unsure.
What time zone does 628 use?
Area code 628 operates on PT (America/Los_Angeles). Numbers in this area code follow standard California time-zone rules including any daylight-saving transitions for that region.
Can I look up a specific 628 phone number?
Yes. Use the reverse lookup widget above to enter a full 628 number. NumLocation returns the line type (mobile, landline, VoIP), carrier, rate-center city, and any public listings tied to the number — free.
What's the difference between 628 and 415?
628 and 415 cover the same California geographic area as overlay codes. Calls between them are local, but you must dial all 10 digits. New phone numbers in this region are assigned from either pool depending on what's available with the carrier at signup.