Local Calling Guide

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

NXX: 917

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
503-917 A Dallas OR PTLJORIY0MD  6529 T-MOBILE USA, INC. 672      
503-917 0 Dallas OR   076F BANDWIDTH.COM CLEC, LLC - OR 672   2014-06-13   
503-917 1 Dallas OR   6529 T-MOBILE USA, INC. 672      
503-917 2 Dallas OR   7172 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 672   2014-04-30   
503-917 3 Dallas OR   750E ONVOY, LLC - OR 672   2015-04-07   
503-917 4 Dallas OR   076F BANDWIDTH.COM CLEC, LLC - OR 672   2015-05-23   
503-917 5 Dallas OR   076F BANDWIDTH.COM CLEC, LLC - OR 672   2015-05-23   
503-917 6 Dallas OR   7531 TELEPORT COMMUNICATIONS AMERICA, LLC - OR 672   2013-01-02   
503-917 7 Dallas OR   936F ASTOUND BROADBAND, LLC - OR 672   2015-03-15   
503-917 8 Dallas OR   6010 NEW CINGULAR WIRELESS PCS, LLC 672   2015-06-15   
503-917 9 Dallas OR   6529 T-MOBILE USA, INC. 672      

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

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