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: 578

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-578 A Newton MA BSTPMALLZMD  506J TWILIO INTERNATIONAL, INC. 128      
857-578 0 Newton MA   892D ONVOY, LLC - MA 128   2021-08-14   
857-578 1 Newton MA   892D ONVOY, LLC - MA 128   2021-07-10   
857-578 2 Newton MA   892D ONVOY, LLC - MA 128   2021-02-28   
857-578 3 Newton MA   892D ONVOY, LLC - MA 128   2021-02-28   
857-578 4 Newton MA   892D ONVOY, LLC - MA 128   2021-02-28   
857-578 5 Newton MA   506J TWILIO INTERNATIONAL, INC. 128   2020-12-11   
857-578 6 Newton MA   892D ONVOY, LLC - MA 128   2021-02-28   
857-578 7 Newton MA   892D ONVOY, LLC - MA 128   2021-07-10   
857-578 8 Newton MA   892D ONVOY, LLC - MA 128   2021-07-10   
857-578 9 Newton MA   892D ONVOY, LLC - MA 128   2021-07-10   

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

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