Prefix 303-218 — Denver, CO

NANPA CO code assignment, current as of July 28, 2026.

A phone number starting 303-218 was issued in the Denver rate center of CO — part of area code 303.

Code-holder of record: MCIMETRO ACCESS TRANSMISSION SERVICES LLC (OCN 7229). The prefix is pooled: its ten thousands-blocks can be shared among several carriers, so different 303-218 numbers may be served by different companies.

A scammer can display 303-218 without ever touching CO. When in doubt, end the call and reach the company or agency through its official website; unwanted robocalls belong in the FTC's fraud report queue.

Denver is part of the Denver-Aurora-Centennial, CO Metropolitan Statistical Area. For routing purposes it sits in LATA 656. Numbers here keep Mountain time.

Neighboring prefixes

FAQ

Where is 303-218 located?

The prefix is assigned to the Denver rate center in CO, area code 303. It is part of the Denver-Aurora-Centennial, CO Metropolitan Statistical Area.

Which company owns 303-218 numbers?

MCIMETRO ACCESS TRANSMISSION SERVICES LLC holds the code, but the prefix is pooled — individual thousands-blocks can be assigned to other carriers, and numbers may be ported to any provider.

Is a call from 303-218 safe to answer?

The prefix itself says nothing about the caller. Legitimate Denver businesses and spoofed robocalls can both display it. Never share personal data with an unverified inbound caller.