Browse the Boulder phone book to find residents and businesses throughout Boulder County. If you received a call from an unrecognized number with area code 303, 720, or 983, 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 Boulder 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.
Colorado phone numbers use area codes 303, and 720. Select a code below to look up numbers starting with it.
According to the National Do Not Call Registry, Colorado residents filed 41,173 complaints about unwanted calls in 2024:
Phone numbers reported to the FTC as unwanted calls by Boulder residents in the last 30 days.
+1 (304) 772-9493
Dropped call or no message
2 reports ·
+1 (304) 307-1432
No Subject Provided
1 report ·
+1 (205) 245-6344
No Subject Provided
1 report ·
+1 (334) 933-2260
Other
1 report ·
+1 (470) 697-6518
Other
1 report ·
+1 (502) 273-8650
Other
1 report ·
+1 (346) 645-6996
Reducing your debt (credit cards, mortgage, student loans)
1 report ·
+1 (303) 616-9946
Calls pretending to be government, businesses, or family and friends
1 report ·
+1 (217) 834-9347
Reducing your debt (credit cards, mortgage, student loans)
1 report ·
+1 (772) 807-3926
Reducing your debt (credit cards, mortgage, student loans)
1 report ·
Received a call from a business but aren't sure it's really them? Boulder County, according to U.S. Census Bureau data, includes 11,943 firms and 12,985 establishments employing 157,001 people.
| County | Percent of City | Firms | Establishments |
|---|---|---|---|
| Boulder | 100.00% | 11943 | 12985 |
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:
Boulder has a population of 108250 people (median age of 28.80) - 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 Boulder County, Colorado state, and other public records.