Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 617 [Rate centres in NPA 617] [Dial plan for NPA 617]

NXX: 397

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-397 A Cambridge MA BRTNMACOVMD  7135 TC SYSTEMS, INC. 128      
617-397 0 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2021-11-01   
617-397 1 Cambridge MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2021-02-23   
617-397 2 Cambridge MA BRTNMACOVMD  7135 TC SYSTEMS, INC. 128      
617-397 3 Cambridge MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2019-12-06   
617-397 4 Cambridge MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2019-12-06   
617-397 5 Cambridge MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2019-12-06   
617-397 6 Cambridge MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2021-11-06   
617-397 7 Cambridge MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2019-12-06   
617-397 8 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2019-10-01   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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