Local Calling Guide

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NPA: 503 [Rate centres in NPA 503] [Dial plan for NPA 503]

NXX: 923

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
503-923 A Beaverton OR PTLDORPBDS7  647F ELTOPIA COMMUNICATIONS LLC - OR 672      

Last updated: Sun, 17 May 2026 03:26:51 UTC

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