Local Calling Guide

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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 820

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-820 A Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-820 0 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2012-02-23   
301-820 1 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2012-02-23   
301-820 2 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2010-09-14   
301-820 3 Gaithersburg MD   829J PAETEC ITEL, LLC 236   2011-05-27   
301-820 4 Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-820 5 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2009-11-04   
301-820 6 Gaithersburg MD WASHDCTTDS0  7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236      
301-820 7 Gaithersburg MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2011-06-17   
301-820 8 Gaithersburg MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2012-02-23   
301-820 9 Gaithersburg MD WASHDCSWMMD  624H ONVOY SPECTRUM, LLC 236   2022-01-07   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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