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: 336

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-336 A Winthrop MA BSTPMALLDS3  892D ONVOY, LLC - MA 128      
857-336 0 Winthrop MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2016-04-30   
857-336 1 Winthrop MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2016-04-30   
857-336 2 Winthrop MA CMBRMABEQMD  321J HD CARRIER LLC 128   2016-05-01   
857-336 3 Winthrop MA CMBRMABEQMD  321J HD CARRIER LLC 128   2016-05-01   
857-336 4 Winthrop MA CMBRMABEQMD  321J HD CARRIER LLC 128   2016-05-01   
857-336 5 Winthrop MA CMBRMABEQMD  321J HD CARRIER LLC 128   2016-05-01   
857-336 6 Winthrop MA BSTNMABLOMD  990E BANDWIDTH.COM CLEC, LLC - MA 128   2016-07-16   
857-336 8 Winthrop MA   515J IP HORIZON LLC 128   2016-07-01   
857-336 9 Winthrop MA CMBRMABEQMD  321J HD CARRIER LLC 128   2016-09-03   

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

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