Local Calling Guide

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

NXX: 837

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
503-837 A Dallas OR PTLDORWADS2  750E ONVOY, LLC - OR 672      
503-837 0 Dallas OR   750E ONVOY, LLC - OR 672   2006-06-18   
503-837 1 Dallas OR   750E ONVOY, LLC - OR 672   2009-02-26   
503-837 2 Dallas OR   076F BANDWIDTH.COM CLEC, LLC - OR 672   2013-01-24   
503-837 3 Dallas OR   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 672   2007-06-15   
503-837 4 Dallas OR   750E ONVOY, LLC - OR 672   2012-12-17   
503-837 5 Dallas OR   750E ONVOY, LLC - OR 672   2012-12-17   
503-837 6 Dallas OR   750E ONVOY, LLC - OR 672   2006-10-12   
503-837 7 Dallas OR   750E ONVOY, LLC - OR 672   2012-12-17   
503-837 8 Dallas OR   157F PEERLESS NETWORK OF OREGON, LLC - OR 672   2013-11-28   
503-837 9 Dallas OR   6010 NEW CINGULAR WIRELESS PCS, LLC 672   2013-10-24   

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

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