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: 370

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-370 A Brookline MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
857-370 0 Brookline MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2021-06-05   
857-370 1 Brookline MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2021-06-05   
857-370 2 Brookline MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2021-06-05   
857-370 3 Brookline MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2021-07-10   
857-370 4 Brookline MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2021-07-10   
857-370 5 Brookline MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2021-07-10   
857-370 6 Brookline MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2021-07-10   
857-370 7 Brookline MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2021-09-17   
857-370 8 Brookline MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2021-05-10   
857-370 9 Brookline MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2021-05-10   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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