Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 503 [Rate centres in NPA 503] [Dial plan for NPA 503]

NXX: 573

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
503-573 A Gresham OR   3234 LEVEL 3 COMMUNICATIONS, LLC - OR 672      
503-573 0 Gresham OR   750E ONVOY, LLC - OR 672   2024-12-15   
503-573 1 Gresham OR   6010 NEW CINGULAR WIRELESS PCS, LLC 672   2024-12-30   
503-573 2 Gresham OR   3234 LEVEL 3 COMMUNICATIONS, LLC - OR 672      
503-573 3 Gresham OR   318J COMCAST IP PHONE, LLC 672   2020-10-02   
503-573 4 Gresham OR   3234 LEVEL 3 COMMUNICATIONS, LLC - OR 672      
503-573 5 Gresham OR   3234 LEVEL 3 COMMUNICATIONS, LLC - OR 672      
503-573 6 Gresham OR   3234 LEVEL 3 COMMUNICATIONS, LLC - OR 672      
503-573 7 Gresham OR   5562 METROPCS, INC. 672   2016-08-25   
503-573 8 Gresham OR   3234 LEVEL 3 COMMUNICATIONS, LLC - OR 672   2011-08-19   
503-573 9 Gresham OR   5562 METROPCS, INC. 672   2014-11-09   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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