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: 239

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-239 A Boston MA BSTPMALLDS3  892D ONVOY, LLC - MA 128      
857-239 0 Boston MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2010-06-19   
857-239 1 Boston MA   892D ONVOY, LLC - MA 128   2010-03-01   
857-239 2 Boston MA   892D ONVOY, LLC - MA 128   2010-03-01   
857-239 3 Boston MA   9102 VERIZON NEW ENGLAND INC. 128   2010-06-15   
857-239 4 Boston MA   9102 VERIZON NEW ENGLAND INC. 128   2010-06-15   
857-239 5 Boston MA   829J PAETEC ITEL, LLC 128   2010-06-09   
857-239 6 Boston MA   9102 VERIZON NEW ENGLAND INC. 128   2010-06-15   
857-239 7 Boston MA   829J PAETEC ITEL, LLC 128   2010-03-24   
857-239 8 Boston MA   318J COMCAST IP PHONE, LLC 128   2010-09-22   
857-239 9 Boston MA   318J COMCAST IP PHONE, LLC 128   2010-09-22   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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