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: 770

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-770 A Boston MA CMBRMABEEMD  116E INTRADO COMMUNICATIONS, LLC 128      
857-770 0 Boston MA CMBRMABEEMD  116E INTRADO COMMUNICATIONS, LLC 128   2015-02-21   
857-770 1 Boston MA BSTNMABLOMD  990E BANDWIDTH.COM CLEC, LLC - MA 128   2015-05-15   
857-770 2 Boston MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2015-05-16   
857-770 3 Boston MA   829J PAETEC ITEL, LLC 128   2015-06-18   
857-770 4 Boston MA   829J PAETEC ITEL, LLC 128   2015-06-18   
857-770 5 Boston MA   829J PAETEC ITEL, LLC 128   2015-06-18   
857-770 6 Boston MA   829J PAETEC ITEL, LLC 128   2015-06-18   
857-770 7 Boston MA   829J PAETEC ITEL, LLC 128   2015-06-18   
857-770 8 Boston MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2015-07-23   
857-770 9 Boston MA CMBRMABEEMD  116E INTRADO COMMUNICATIONS, LLC 128   2015-02-21   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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