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: 275

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
508-275 A Holliston MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
508-275 0 Holliston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
508-275 2 Holliston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
508-275 3 Holliston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
508-275 4 Holliston MA   624H ONVOY SPECTRUM, LLC 128   2021-12-20   
508-275 5 Holliston MA   508J CENTURYLINK COMMUNICATIONS, LLC 128   2014-06-20   
508-275 6 Holliston MA   624H ONVOY SPECTRUM, LLC 128   2021-12-20   
508-275 8 Holliston MA   624H ONVOY SPECTRUM, LLC 128   2021-12-20   
508-275 9 Holliston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      

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

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