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: 231

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-231 A Watertown MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-231 0 Watertown MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-231 1 Watertown MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-231 2 Watertown MA CMBRMA01DS5  7135 TC SYSTEMS, INC. 128   2002-07-09   
617-231 3 Watertown MA BRTNMACOX2X  829J PAETEC ITEL, LLC 128   2005-02-24   
617-231 4 Watertown MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-231 6 Watertown MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-231 7 Watertown MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2013-09-16   
617-231 8 Watertown MA BRTNMACOX2X  829J PAETEC ITEL, LLC 128   2010-12-03   
617-231 9 Watertown MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2020-06-21   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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