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: 323

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
571-323 A Herndon VA   829J PAETEC ITEL, LLC 236   2025-04-02   

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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