Prefix 503-328 — Gresham, OR
The 503-328 prefix belongs to area code 503 and is anchored to the Gresham rate center (OR). In NANP terms, the prefix — or NXX — determines the rate center a number is billed against.
Gresham is part of the Portland-Vancouver-Hillsboro, OR-WA Metropolitan Statistical Area. For routing purposes it sits in LATA 672. Numbers here keep Pacific time.
The assigned code holder is ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM, operating company number 7172. This is a pooled prefix — expect numbers within it to be split across more than one carrier in 1,000-number blocks.
Caller ID showing 503-328 is not proof the call came from Gresham: spoofing and porting both detach numbers from their origin. To verify a caller, hang up and dial the organization's published number, and report suspicious calls to the FTC.
Neighboring prefixes
| Prefix | Rate center | Code holder |
|---|---|---|
| 503-325 | Astoria | QWEST CORPORATION |
| 503-326 | Portland | QWEST CORPORATION |
| 503-327 | Portland | TELEPORT COMMUNICATIONS AMERICA, LLC - OR |
| 503-329 | Portland | NEW CINGULAR WIRELESS PCS, LLC |
| 503-330 | Beaverton | METROPCS, INC. |
| 503-331 | Portland | QWEST CORPORATION |
FAQ
Where is 503-328 located?
The prefix is assigned to the Gresham rate center in OR, area code 503. It is part of the Portland-Vancouver-Hillsboro, OR-WA Metropolitan Statistical Area.
Which company owns 503-328 numbers?
ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 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 503-328 safe to answer?
The prefix itself says nothing about the caller. Legitimate Gresham businesses and spoofed robocalls can both display it. Never share personal data with an unverified inbound caller.