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: 613

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-613 A Cambridge MA CMBRMA01DS5  7135 TC SYSTEMS, INC. 128      

Last updated: Tue, 07 Oct 2025 16:47:53 UTC

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