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: 391

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-391 A Boston MA   829J PAETEC ITEL, LLC 128      
617-391 0 Boston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2008-06-16   
617-391 1 Boston MA   829J PAETEC ITEL, LLC 128   2008-06-14   
617-391 2 Boston MA   829J PAETEC ITEL, LLC 128   2008-06-14   
617-391 3 Boston MA   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 128   2008-08-17   
617-391 4 Boston MA   829J PAETEC ITEL, LLC 128   2009-04-01   
617-391 5 Boston MA   829J PAETEC ITEL, LLC 128   2008-07-03   
617-391 6 Boston MA   829J PAETEC ITEL, LLC 128   2008-07-03   
617-391 7 Boston MA   316E YMAX COMMUNICATIONS CORP. - MA 128   2008-07-18   
617-391 8 Boston MA   316E YMAX COMMUNICATIONS CORP. - MA 128   2008-07-18   
617-391 9 Boston MA   671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 128   2008-07-18   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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