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: 737

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-737 A Watertown MA SOVLMAABCMD  516J TON80 COMMUNICATIONS, LLC 128      
857-737 0 Watertown MA   892D ONVOY, LLC - MA 128   2023-08-17   
857-737 1 Watertown MA   892D ONVOY, LLC - MA 128   2023-08-17   
857-737 2 Watertown MA   892D ONVOY, LLC - MA 128   2023-07-08   
857-737 3 Watertown MA   892D ONVOY, LLC - MA 128   2023-07-08   
857-737 4 Watertown MA   624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-737 7 Watertown MA   516J TON80 COMMUNICATIONS, LLC 128   2022-05-26   
857-737 8 Watertown MA   892D ONVOY, LLC - MA 128   2022-05-27   
857-737 9 Watertown MA   892D ONVOY, LLC - MA 128   2024-03-08   

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

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