Local Calling Guide

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

NXX: 240

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-240 A Herndon VA BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
571-240 0 Herndon VA   138E ONVOY, LLC - VA 236   2024-01-18   
571-240 1 Herndon VA   073H TELNYX LLC 236   2024-01-26   
571-240 2 Herndon VA   138E ONVOY, LLC - VA 236   2024-04-11   
571-240 3 Herndon VA   073H TELNYX LLC 236   2024-04-19   
571-240 4 Herndon VA   138E ONVOY, LLC - VA 236   2024-04-15   
571-240 5 Herndon VA   138E ONVOY, LLC - VA 236   2024-04-15   
571-240 6 Herndon VA   079F BANDWIDTH.COM CLEC, LLC - VA 236   2024-06-09   
571-240 7 Herndon VA   079F BANDWIDTH.COM CLEC, LLC - VA 236   2024-06-09   
571-240 8 Herndon VA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2023-11-16   
571-240 9 Herndon VA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2023-11-16   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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