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: 645

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
508-645 A Chilmark MA CHLMMASTRS1  9102 VERIZON NEW ENGLAND INC. 128      
508-645 0 Chilmark MA   892D ONVOY, LLC - MA 128   2016-04-04   
508-645 2 Chilmark MA   9102 VERIZON NEW ENGLAND INC. 128      
508-645 3 Chilmark MA   9102 VERIZON NEW ENGLAND INC. 128      
508-645 4 Chilmark MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2004-09-07   
508-645 5 Chilmark MA   9102 VERIZON NEW ENGLAND INC. 128      
508-645 6 Chilmark MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2010-02-22   
508-645 7 Chilmark MA   9102 VERIZON NEW ENGLAND INC. 128      
508-645 8 Chilmark MA   892D ONVOY, LLC - MA 128   2016-04-04   
508-645 9 Chilmark MA   9102 VERIZON NEW ENGLAND INC. 128      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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