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: 799

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-799 A Cambridge MA CMBRMABEQMD  321J HD CARRIER LLC 128      
857-799 9 Cambridge MA   321J HD CARRIER LLC 128   2018-12-29   

Last updated: Sun, 04 Apr 2021 19:28:27 UTC

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