Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 571 [Rate centres in NPA 571] [Dial plan for NPA 571]

NXX: 720

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-720 A Herndon VA   138E ONVOY, LLC - VA 236   2025-05-10   
571-720 0 Herndon VA   138E ONVOY, LLC - VA 236   2025-05-10   
571-720 1 Herndon VA   079F BANDWIDTH.COM CLEC, LLC - VA 236   2025-05-12   
571-720 6 Herndon VA   073H TELNYX LLC 236   2025-06-27   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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