Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 641 [Rate centres in NPA 641] [Dial plan for NPA 641]

NXX: 857

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
641-857 A Dumont IA DUMTIAXODS0  1152 DUMONT TEL. CO. 632      

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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