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: 991

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-991 A Boston MA BSTPMALLPS0  6101 COMCAST PHONE OF MASSACHUSETTS, INC. - MA 128      
857-991 0 Boston MA   6664 SPRINT SPECTRUM L.P. 128   2003-12-29   
857-991 1 Boston MA   6101 COMCAST PHONE OF MASSACHUSETTS, INC. - MA 128   2002-07-29   
857-991 2 Boston MA   6664 SPRINT SPECTRUM L.P. 128   2003-12-29   
857-991 3 Boston MA   6664 SPRINT SPECTRUM L.P. 128   2003-12-29   
857-991 4 Boston MA   6664 SPRINT SPECTRUM L.P. 128   2004-08-10   
857-991 5 Boston MA   6664 SPRINT SPECTRUM L.P. 128   2004-08-10   
857-991 6 Boston MA   6889 OMNIPOINT MIAMI E LICENSE, LLC DBA T-MOBILE USA 128   2003-12-02   
857-991 7 Boston MA   6889 OMNIPOINT MIAMI E LICENSE, LLC DBA T-MOBILE USA 128   2003-12-02   
857-991 8 Boston MA   6889 OMNIPOINT MIAMI E LICENSE, LLC DBA T-MOBILE USA 128   2004-08-09   
857-991 9 Boston MA   6889 OMNIPOINT MIAMI E LICENSE, LLC DBA T-MOBILE USA 128   2003-12-13   

Last updated: Sat, 31 Oct 2020 19:28:10 UTC

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