Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 223 [Rate centres in NPA 223] [Dial plan for NPA 223]

NXX: 331

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
223-331 A Adamstown PA EPHRPAXE4MD  547E ONVOY, LLC - PA 226      
223-331 1 Adamstown PA   145J TERRA NOVA TELECOM INC. 226   2025-07-10   
223-331 2 Adamstown PA   547E ONVOY, LLC - PA 226   2023-11-13   
223-331 9 Adamstown PA   624H ONVOY SPECTRUM, LLC 226   2024-03-02   

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

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