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: 377

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
508-377 A Milford MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
508-377 0 Milford MA   6387 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 128   2025-12-17   
508-377 1 Milford MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2005-12-17   
508-377 2 Milford MA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2008-11-06   
508-377 3 Milford MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2010-02-21   
508-377 4 Milford MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
508-377 5 Milford MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
508-377 6 Milford MA   624H ONVOY SPECTRUM, LLC 128   2021-12-20   
508-377 7 Milford MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
508-377 8 Milford MA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2009-03-02   
508-377 9 Milford MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      

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

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