Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 610 [Rate centres in NPA 610] [Dial plan for NPA 610]

NXX: 351

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
610-351 A Allentown (Lehigh) PA NATNPAAGGT0  7615 RCN TELECOM SERVICES OF PENNSYLVANIA, INC. 228      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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