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: 323

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-323 A Chelsea MA CHLSMACHDS0  9102 VERIZON NEW ENGLAND INC. 128      
857-323 0 Chelsea MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2013-04-21   
857-323 1 Chelsea MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2014-10-16   
857-323 2 Chelsea MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2015-05-17   
857-323 3 Chelsea MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2015-05-17   
857-323 4 Chelsea MA   732H BARR TELL USA, INC. - MA 128   2015-12-31   
857-323 5 Chelsea MA   892D ONVOY, LLC - MA 128   2014-10-10   
857-323 6 Chelsea MA   892D ONVOY, LLC - MA 128   2014-10-10   
857-323 7 Chelsea MA   508J CENTURYLINK COMMUNICATIONS, LLC 128   2013-09-30   
857-323 8 Chelsea MA   9102 VERIZON NEW ENGLAND INC. 128   2013-03-15   
857-323 9 Chelsea MA   892D ONVOY, LLC - MA 128   2016-02-29   

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

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