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: 300

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
503-300 A Bay City OR   792K CHARTER IP ENABLED SERVICES, LLC 672      
503-300 0 Bay City OR   792K CHARTER IP ENABLED SERVICES, LLC 672      
503-300 1 Bay City OR   750E ONVOY, LLC - OR 672   2020-02-22   
503-300 2 Bay City OR   750E ONVOY, LLC - OR 672   2020-02-22   
503-300 3 Bay City OR   936F ASTOUND BROADBAND, LLC - OR 672   2017-12-04   
503-300 4 Bay City OR   750E ONVOY, LLC - OR 672   2019-11-08   
503-300 5 Bay City OR   750E ONVOY, LLC - OR 672   2018-12-06   
503-300 6 Bay City OR   750E ONVOY, LLC - OR 672   2019-11-08   
503-300 7 Bay City OR   508J CENTURYLINK COMMUNICATIONS, LLC 672   2013-11-27   
503-300 8 Bay City OR   6010 NEW CINGULAR WIRELESS PCS, LLC 672   2019-06-26   
503-300 9 Bay City OR   6010 NEW CINGULAR WIRELESS PCS, LLC 672   2016-01-06   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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