Browse the San Mateo phone book to find residents and businesses throughout San Mateo County. If you received a call from an unrecognized number with area code 650, use our lookup tool to see who it belongs to before you call back.
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Find phone numbers for city businesses, public services, and organizations by category.
Got a phone call or message from a San Mateo phone number you don't recognize? Before you answer, call back, or reply, use our phone number lookup service to find out who called you.
California phone numbers use area codes 650. Select a code below to look up numbers starting with it.
According to the National Do Not Call Registry, California residents filed 287,916 complaints about unwanted calls in 2024:
Phone numbers reported to the FTC as unwanted calls by San Mateo residents in the last 30 days.
+1 (888) 269-4978
Reducing your debt (credit cards, mortgage, student loans)
2 reports ·
+1 (951) 763-6773
Reducing your debt (credit cards, mortgage, student loans)
1 report ·
+1 (206) 758-9771
Other
1 report ·
+1 (206) 758-9193
Other
1 report ·
+1 (650) 606-6584
Other
1 report ·
+1 (714) 534-8735
Other
1 report ·
+1 (419) 600-6950
Other
1 report ·
+1 (302) 232-7983
Other
1 report ·
+1 (341) 215-9626
Reducing your debt (credit cards, mortgage, student loans)
1 report ·
+1 (341) 202-7173
Other
1 report ·
Received a call from a business but aren't sure it's really them? San Mateo County, according to U.S. Census Bureau data, includes 18,903 firms and 21,632 establishments employing 464,365 people.
| County | Percent of City | Firms | Establishments |
|---|---|---|---|
| San Mateo | 100.00% | 18903 | 21632 |
Use our reverse lookup service to verify whether a number belongs to a legitimate local business, not scammers spoofing local numbers to gain your trust.
If you receive fraudulent calls or suspect a scam attempt, report it to reportfraud.ftc.gov or local police department using the following contacts:
San Mateo has a population of 105661 people (median age of 37.80) - thousands of potential callers you might not recognize: neighbors, an old contact, or someone you actually want to talk to. Use our local white pages to find residents' phone numbers and addresses sourced from San Mateo County, California state, and other public records.