Local Calling Guide

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

NXX: 355

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-355 A Gaithersburg MD GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236      
301-355 0 Gaithersburg MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2009-10-12   
301-355 1 Gaithersburg MD WASJDCDCDS0  6050 GLOBAL CROSSING LOCAL SERVICES, INC. - MD 236   2009-11-30   
301-355 2 Gaithersburg MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2011-01-22   
301-355 3 Gaithersburg MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2008-10-05   
301-355 4 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2009-08-28   
301-355 5 Gaithersburg MD GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236   2007-09-04   
301-355 6 Gaithersburg MD GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236   2007-09-04   
301-355 7 Gaithersburg MD GTBGMDGBPS0  9212 VERIZON MARYLAND, INC. 236   2007-09-04   
301-355 8 Gaithersburg MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236   2009-08-28   
301-355 9 Gaithersburg MD WASLDCRGDS0  281E YMAX COMMUNICATIONS CORP. - MD 236   2011-02-02   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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