Local Calling Guide

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NPA: 571 [Rate centres in NPA 571] [Dial plan for NPA 571]

NXX: 306

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-306 A Herndon VA WASHDCDP8MD  079F BANDWIDTH.COM CLEC, LLC - VA 236      
571-306 0 Herndon VA WASHDCDP8MD  079F BANDWIDTH.COM CLEC, LLC - VA 236   2010-04-11   
571-306 1 Herndon VA WASHDCDP8MD  079F BANDWIDTH.COM CLEC, LLC - VA 236   2010-04-11   
571-306 2 Herndon VA WASHDCDP8MD  079F BANDWIDTH.COM CLEC, LLC - VA 236   2010-04-11   
571-306 3 Herndon VA WASHDCDP8MD  079F BANDWIDTH.COM CLEC, LLC - VA 236   2010-04-11   
571-306 4 Herndon VA MCLNVA23DS4  8825 LEVEL 3 COMMUNICATIONS, LLC - VA 236   2011-05-16   
571-306 5 Herndon VA WASKDCFNPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2011-06-09   
571-306 6 Herndon VA   7529 TELEPORT COMMUNICATIONS AMERICA, LLC - DC 236   2011-05-27   
571-306 7 Herndon VA   318J COMCAST IP PHONE, LLC 236   2012-01-13   
571-306 8 Herndon VA BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2011-06-07   
571-306 9 Herndon VA BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2011-06-07   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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