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]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-999 4 Cambridge MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2014-09-15   
857-999 5 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2013-12-03   
857-999 6 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2013-12-03   
857-999 7 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2013-12-03   
857-999 8 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2013-12-03   
857-999 9 Cambridge MA SOVLMAABDS2  268F PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA 128   2012-07-14   

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Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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