Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 401 [Rate centres in NPA 401] [Dial plan for NPA 401]

NXX: 637

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
401-637 A Westerly RI PRVDRIWAHMD  318J COMCAST IP PHONE, LLC 130      
401-637 0 Westerly RI   977E ONVOY, LLC - RI 130   2023-08-09   
401-637 1 Westerly RI   977E ONVOY, LLC - RI 130   2023-08-09   
401-637 4 Westerly RI   318J COMCAST IP PHONE, LLC 130   2007-09-14   
401-637 7 Westerly RI   318J COMCAST IP PHONE, LLC 130   2010-05-18   

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

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