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: 251

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
401-251 A Portsmouth RI   507J THE VOICE APPLICATION NETWORK, LLC 130   2025-04-11   
401-251 0 Portsmouth RI   631G PEERLESS NETWORK OF RHODE ISLAND, LLC - RI 130   2020-03-23   
401-251 1 Portsmouth RI   507J THE VOICE APPLICATION NETWORK, LLC 130   2016-11-26   
401-251 2 Portsmouth RI   977E ONVOY, LLC - RI 130   2020-06-12   
401-251 3 Portsmouth RI   977E ONVOY, LLC - RI 130   2020-06-12   
401-251 4 Portsmouth RI   318J COMCAST IP PHONE, LLC 130   2018-03-10   
401-251 6 Portsmouth RI   977E ONVOY, LLC - RI 130   2023-02-11   
401-251 7 Portsmouth RI   977E ONVOY, LLC - RI 130   2022-09-29   
401-251 8 Portsmouth RI   073H TELNYX LLC 130   2023-02-23   
401-251 9 Portsmouth RI   073H TELNYX LLC 130   2023-06-24   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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