Prefix 503-303 — Clackamas, OR
Numbers in the 503-303 prefix are registered to the Clackamas rate center in OR, inside area code 503. The prefix is the second block of a ten-digit US number (503-303-XXXX) and pins the number to a billing locality.
The assigned code holder is MCIMETRO ACCESS TRANSMISSION SERVICES LLC, operating company number 7229. This is a pooled prefix — expect numbers within it to be split across more than one carrier in 1,000-number blocks.
The rate center lies in the Portland-Vancouver-Hillsboro, OR-WA Metropolitan Statistical Area. The serving LATA is 672. Local time follows the Pacific zone.
Spoofing means this prefix on your screen doesn't guarantee a Clackamas caller. Verify independently before trusting a request for money or data.
Neighboring prefixes
| Prefix | Rate center | Code holder |
|---|---|---|
| 503-300 | Bay City | CHARTER IP ENABLED SERVICES, LLC |
| 503-301 | Portland | SPOK, INC. |
| 503-302 | Salem | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - OR |
| 503-304 | Salem | QWEST CORPORATION |
| 503-305 | Clackamas | MCIMETRO ACCESS TRANSMISSION SERVICES LLC |
| 503-306 | Portland | QWEST CORPORATION |
FAQ
Where is 503-303 located?
The prefix is assigned to the Clackamas rate center in OR, area code 503. It is part of the Portland-Vancouver-Hillsboro, OR-WA Metropolitan Statistical Area.
Which company owns 503-303 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 503-303 safe to answer?
The prefix itself says nothing about the caller. Legitimate Clackamas businesses and spoofed robocalls can both display it. Never share personal data with an unverified inbound caller.