Local Calling Guide

Area code/prefix search

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NPA: 857 [Rate centres in NPA 857] [Dial plan for NPA 857]

NXX: 367

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-367 A Watertown MA CMBRMA01DS5  7135 TC SYSTEMS, INC. 128      
857-367 0 Watertown MA   892D ONVOY, LLC - MA 128   2021-03-06   
857-367 1 Watertown MA   892D ONVOY, LLC - MA 128   2021-03-06   
857-367 2 Watertown MA   892D ONVOY, LLC - MA 128   2021-03-06   
857-367 3 Watertown MA   624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-367 4 Watertown MA   892D ONVOY, LLC - MA 128   2021-04-06   
857-367 5 Watertown MA   624H ONVOY SPECTRUM, LLC 128   2021-04-15   
857-367 6 Watertown MA   7135 TC SYSTEMS, INC. 128   2020-12-07   
857-367 7 Watertown MA   7135 TC SYSTEMS, INC. 128   2021-02-26   
857-367 8 Watertown MA   892D ONVOY, LLC - MA 128   2021-04-06   
857-367 9 Watertown MA   892D ONVOY, LLC - MA 128   2021-04-06   

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

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