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: 577

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-577 A Charlestown MA BSTPMALLDS3  892D ONVOY, LLC - MA 128      
857-577 0 Charlestown MA   321J HD CARRIER LLC 128   2016-04-12   
857-577 1 Charlestown MA   321J HD CARRIER LLC 128   2016-04-12   
857-577 2 Charlestown MA   321J HD CARRIER LLC 128   2016-04-12   
857-577 3 Charlestown MA   321J HD CARRIER LLC 128   2016-04-12   
857-577 4 Charlestown MA   321J HD CARRIER LLC 128   2016-04-12   
857-577 5 Charlestown MA   321J HD CARRIER LLC 128   2016-04-12   
857-577 6 Charlestown MA   321J HD CARRIER LLC 128   2016-04-12   
857-577 7 Charlestown MA   892D ONVOY, LLC - MA 128   2016-04-11   
857-577 8 Charlestown MA   892D ONVOY, LLC - MA 128   2016-04-11   
857-577 9 Charlestown MA   321J HD CARRIER LLC 128   2016-04-12   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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