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: 847

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-847 A Dorchester MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128      
857-847 0 Dorchester MA   892D ONVOY, LLC - MA 128   2021-06-13   
857-847 1 Dorchester MA   892D ONVOY, LLC - MA 128   2021-06-13   
857-847 2 Dorchester MA   892D ONVOY, LLC - MA 128   2021-06-13   
857-847 3 Dorchester MA   892D ONVOY, LLC - MA 128   2021-05-18   
857-847 4 Dorchester MA   892D ONVOY, LLC - MA 128   2021-05-18   
857-847 5 Dorchester MA   892D ONVOY, LLC - MA 128   2021-05-18   
857-847 6 Dorchester MA   892D ONVOY, LLC - MA 128   2021-05-18   
857-847 7 Dorchester MA   624H ONVOY SPECTRUM, LLC 128   2021-05-17   
857-847 8 Dorchester MA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2023-09-08   
857-847 9 Dorchester MA   892D ONVOY, LLC - MA 128   2021-06-13   

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

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