Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 857 [Rate centres in NPA 857] [Dial plan for NPA 857]

NXX: 678

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-678 A Belmont MA   566J RADIANTIQ LLC 128   2021-06-04   
857-678 7 Belmont MA   566J RADIANTIQ LLC 128   2021-06-04   

Last updated: Tue, 04 May 2021 15:04:27 UTC

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