Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 508 [Rate centres in NPA 508] [Dial plan for NPA 508]

NXX: 938

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
508-938 A Westport MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2025-04-07   
508-938 0 Westport MA   6387 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 128   2025-12-23   
508-938 1 Westport MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2006-01-28   
508-938 2 Westport MA   892D ONVOY, LLC - MA 128   2016-04-11   
508-938 3 Westport MA   624H ONVOY SPECTRUM, LLC 128   2021-05-04   
508-938 4 Westport MA   145J TERRA NOVA TELECOM INC. 128   2025-04-09   
508-938 5 Westport MA   318J COMCAST IP PHONE, LLC 128   2002-07-05   
508-938 6 Westport MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2004-04-10   
508-938 7 Westport MA   829J PAETEC ITEL, LLC 128   2005-06-20   
508-938 8 Westport MA   624H ONVOY SPECTRUM, LLC 128   2021-12-21   
508-938 9 Westport MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2011-03-12   

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

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