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: 437

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-437 A Roxbury MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
857-437 0 Roxbury MA   892D ONVOY, LLC - MA 128   2020-06-07   
857-437 1 Roxbury MA   892D ONVOY, LLC - MA 128   2020-06-07   
857-437 2 Roxbury MA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2020-07-25   
857-437 3 Roxbury MA   892D ONVOY, LLC - MA 128   2021-01-02   
857-437 4 Roxbury MA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2024-10-05   
857-437 5 Roxbury MA   892D ONVOY, LLC - MA 128   2021-01-02   
857-437 6 Roxbury MA   892D ONVOY, LLC - MA 128   2021-01-02   
857-437 7 Roxbury MA   892D ONVOY, LLC - MA 128   2021-01-02   
857-437 8 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2019-10-27   
857-437 9 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2019-10-27   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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