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: 320

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-320 A Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
857-320 0 Cambridge MA CATNMAAKAMD  6387 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 128   2015-02-01   
857-320 1 Cambridge MA CATNMAAKAMD  6387 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 128   2015-02-01   
857-320 2 Cambridge MA NWTNMAWAVMD  318J COMCAST IP PHONE, LLC 128   2016-05-16   
857-320 3 Cambridge MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2014-12-31   
857-320 4 Cambridge MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2014-12-31   
857-320 5 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2016-10-17   
857-320 6 Cambridge MA CHTWMABF2MD  671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 128   2015-03-30   
857-320 7 Cambridge MA CATNMAAKAMD  6387 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 128   2015-08-16   
857-320 8 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2018-10-07   
857-320 9 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2014-11-28   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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