Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 667 [Rate centres in NPA 667] [Dial plan for NPA 667]

NXX: 523

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
667-523 A Odenton MD   7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238   2025-09-29   
667-523 4 Odenton MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2025-12-08   

Last updated: Sun, 17 May 2026 03:26:51 UTC

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