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: 256

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-256 A Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2024-02-09   
617-256 0 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
617-256 1 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2022-10-21   
617-256 2 Cambridge MA BSTNMABLOMD  990E BANDWIDTH.COM CLEC, LLC - MA 128   2022-11-18   
617-256 3 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
617-256 4 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
617-256 5 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
617-256 6 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
617-256 7 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
617-256 8 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
617-256 9 Cambridge MA   5562 METROPCS, INC. 128      

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

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