Local Calling Guide

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NPA: 857 [Rate centres in NPA 857] [Dial plan for NPA 857]

NXX: 305

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-305 A Boston MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
857-305 0 Boston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2014-05-23   
857-305 1 Boston MA   829J PAETEC ITEL, LLC 128   2014-04-17   
857-305 2 Boston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2013-09-19   
857-305 3 Boston MA   318J COMCAST IP PHONE, LLC 128   2013-10-31   
857-305 4 Boston MA   829J PAETEC ITEL, LLC 128   2013-11-14   
857-305 5 Boston MA   829J PAETEC ITEL, LLC 128   2013-11-14   
857-305 6 Boston MA   892D ONVOY, LLC - MA 128   2014-09-26   
857-305 7 Boston MA   892D ONVOY, LLC - MA 128   2014-09-26   
857-305 8 Boston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2014-05-09   
857-305 9 Boston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2014-05-09   

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

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