Local Calling Guide

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

NXX: 521

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-521 A Herndon VA HRNDVA13AMD  4725 CAVALIER TELEPHONE, LLC - VA 236      
571-521 0 Herndon VA HRNDVA13AMD  4725 CAVALIER TELEPHONE, LLC - VA 236      
571-521 1 Herndon VA HRNDVA13AMD  4725 CAVALIER TELEPHONE, LLC - VA 236      
571-521 2 Herndon VA HRNDVA13AMD  4725 CAVALIER TELEPHONE, LLC - VA 236      
571-521 3 Herndon VA MCLNVA23DS4  8825 LEVEL 3 COMMUNICATIONS, LLC - VA 236   2020-08-21   
571-521 4 Herndon VA ARTNVAARXFY  506J TWILIO INTERNATIONAL, INC. 236   2021-01-02   
571-521 5 Herndon VA HRNDVA13AMD  4725 CAVALIER TELEPHONE, LLC - VA 236      
571-521 6 Herndon VA HRNDVA13AMD  4725 CAVALIER TELEPHONE, LLC - VA 236      
571-521 7 Herndon VA WASHDCINDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 236   2006-03-07   
571-521 8 Herndon VA MCLNVA23DS4  8825 LEVEL 3 COMMUNICATIONS, LLC - VA 236   2006-05-11   
571-521 9 Herndon VA WASKDCFNAMD  6827 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - VA 236   2006-04-27   

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

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