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: 419

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-419 A Milton MA CMBSMA01AMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128      
857-419 0 Milton MA   073H TELNYX LLC 128   2017-04-26   
857-419 1 Milton MA   892D ONVOY, LLC - MA 128   2023-08-17   
857-419 2 Milton MA   624H ONVOY SPECTRUM, LLC 128   2021-04-11   
857-419 3 Milton MA   892D ONVOY, LLC - MA 128   2021-01-03   
857-419 4 Milton MA   268F PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA 128   2018-03-11   
857-419 5 Milton MA   892D ONVOY, LLC - MA 128   2021-01-03   
857-419 6 Milton MA   892D ONVOY, LLC - MA 128   2021-01-03   
857-419 7 Milton MA   892D ONVOY, LLC - MA 128   2019-02-11   
857-419 8 Milton MA   892D ONVOY, LLC - MA 128   2019-02-11   
857-419 9 Milton MA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2016-10-10   

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

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