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: 587

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-587 A Dorchester MA CMBRMABEQMD  321J HD CARRIER LLC 128      
857-587 0 Dorchester MA   892D ONVOY, LLC - MA 128   2016-03-22   
857-587 1 Dorchester MA   892D ONVOY, LLC - MA 128   2016-03-22   
857-587 2 Dorchester MA   321J HD CARRIER LLC 128   2016-05-12   
857-587 3 Dorchester MA   321J HD CARRIER LLC 128   2016-05-12   
857-587 4 Dorchester MA   321J HD CARRIER LLC 128   2016-05-12   
857-587 5 Dorchester MA   321J HD CARRIER LLC 128   2016-05-12   
857-587 6 Dorchester MA   321J HD CARRIER LLC 128   2016-05-12   
857-587 7 Dorchester MA   321J HD CARRIER LLC 128   2016-03-21   
857-587 8 Dorchester MA   321J HD CARRIER LLC 128   2016-05-12   
857-587 9 Dorchester MA   321J HD CARRIER LLC 128   2016-05-12   

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

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