Area Code 303 — Denver, CO

Everything you need to know about area code 303 in Colorado

At a Glance

LOCATION
Denver

Colorado

TIMEZONE
Mountain

Mountain Time Zone

ESTABLISHED
1947

Original area code

POPULATION
~2,500,000

Estimated residents served

STATE
CO

Colorado

TYPE
Geographic

Primary code for this region

Area Code 303: Denver, Colorado

Area code 303 serves Denver, Boulder, and the surrounding Front Range region of Colorado. Originally covering the entire state, it now focuses on the Denver metro area, one of the fastest-growing regions in the country.

Phone numbers with the 303 area code follow the format (303) XXX-XXXX, where the next three digits represent the local exchange. The 303 area code is part of the North American Numbering Plan (NANP) and is regulated by the Federal Communications Commission (FCC).

If you receive a call from a 303 number that you don't recognize, you can search it using the lookup tool above. While the 303 area code legitimately serves millions of residents and businesses in the Denver area, scammers sometimes spoof local area codes to make their calls appear more trustworthy. Always verify unfamiliar numbers before returning calls or sharing personal information.

The Denver region served by area code 303 is one of the most densely populated areas in Colorado. As a primary geographic code, 303 has been the main identifier for this region since the original numbering plan was established.

For detailed information about any phone number in the 303 area code, including owner identification, carrier data, and spam reports, use our search tool above or visit one of our trusted lookup providers.

Areas Served by 303

DenverBoulderAurora

Common Scam Calls from 303 Numbers

These are frequently reported scam patterns from phone numbers using the 303 area code. Scammers often spoof area codes, so a call appearing to come from 303 may originate elsewhere.

GRANDPARENT SCAM

Callers impersonate a grandchild in trouble, claiming to need bail money or emergency funds wired immediately.

PACKAGE DELIVERY SCAM

Automated messages claim a package could not be delivered and direct you to a phishing website to reschedule delivery.

STUDENT LOAN FORGIVENESS

Callers offer fake student loan forgiveness programs, collecting personal and financial information under the pretense of reducing your debt.

Stay Safe: Never share personal information with incoming callers. If suspicious, hang up and search the number above.

Questions About Area Code 303

Area code 303 serves Denver, Colorado. Area code 303 serves Denver, Boulder, and the surrounding Front Range region of Colorado. Originally covering the entire state, it now focuses on the Denver metro area, one of the fastest-growing regions in the country.

Area code 303 is in the Mountain timezone. Calls from 303 numbers originate from the Denver region.

Not necessarily. Area code 303 serves many people in Denver. However, scammers can spoof any area code. If you receive a suspicious call from a 303 number, search it above before calling back.

Area code 303 was one of the original area codes established in 1947. It serves as the primary geographic code for its region.

Nearby Area Codes

720Denver

Getting Unknown Calls From 303?

If you received an unknown call from a 303 number, use our dedicated lookup page to identify the caller and check for scam reports.

Who Called Me From 303? →
Caller Id Explained → One Ring Scam → What Is Stir Shaken Simple →

Search a 303 Number

Enter any 303 phone number to check caller identity, spam risk, and more.

Start Searching