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: 822

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-822 A Somerville MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   
857-822 2 Somerville MA   114J EXIANT COMMUNICATIONS LLC 128   2026-09-03   
857-822 6 Somerville MA CMBSMA01AMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2026-06-26   
857-822 7 Somerville MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   
857-822 8 Somerville MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   
857-822 9 Somerville MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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