Local Calling Guide

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

NXX: 854

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
503-854 A Detroit OR DTRTORXARS0  4323 ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 672      
503-854 0 Detroit OR   750E ONVOY, LLC - OR 672   2012-12-17   
503-854 1 Detroit OR   750E ONVOY, LLC - OR 672   2014-01-02   
503-854 2 Detroit OR   647F ELTOPIA COMMUNICATIONS LLC - OR 672   2010-07-17   
503-854 3 Detroit OR   4323 ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 672      
503-854 4 Detroit OR   750E ONVOY, LLC - OR 672   2012-12-17   
503-854 5 Detroit OR   750E ONVOY, LLC - OR 672   2014-01-02   
503-854 6 Detroit OR   750E ONVOY, LLC - OR 672   2010-12-20   
503-854 7 Detroit OR   750E ONVOY, LLC - OR 672   2007-04-15   
503-854 8 Detroit OR   508J CENTURYLINK COMMUNICATIONS, LLC 672   2014-02-17   
503-854 9 Detroit OR   750E ONVOY, LLC - OR 672   2017-11-03   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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