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: 357

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-357 A Cambridge MA CMBRMABEUMD  007J MEGAPHONE INC 128      
857-357 0 Cambridge MA   268F PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA 128   2020-04-13   
857-357 1 Cambridge MA   007J MEGAPHONE INC 128   2020-02-21   
857-357 7 Cambridge MA   892D ONVOY, LLC - MA 128   2020-06-21   
857-357 8 Cambridge MA   892D ONVOY, LLC - MA 128   2020-06-21   

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

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