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: 300

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-300 A Cambridge MA BRTNMACOVMD  7135 TC SYSTEMS, INC. 128      
617-300 0 Cambridge MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2008-02-21   
617-300 1 Cambridge MA BRTNMACOVMD  7135 TC SYSTEMS, INC. 128      
617-300 2 Cambridge MA BRTNMACOVMD  7135 TC SYSTEMS, INC. 128      
617-300 3 Cambridge MA BRTNMACOVMD  7135 TC SYSTEMS, INC. 128      
617-300 4 Cambridge MA BRTNMACOVMD  7135 TC SYSTEMS, INC. 128      
617-300 5 Cambridge MA BRTNMACOVMD  7135 TC SYSTEMS, INC. 128      
617-300 6 Cambridge MA BRTNMACOVMD  7135 TC SYSTEMS, INC. 128      
617-300 7 Cambridge MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2021-02-23   
617-300 8 Cambridge MA CATNMAAKPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 128   2006-12-14   
617-300 9 Cambridge MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2021-11-01   

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

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