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: 557

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
401-557 A Greenwich RI   7351 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 130   2025-08-28   
401-557 5 Greenwich RI   145J TERRA NOVA TELECOM INC. 130   2025-10-16   
401-557 6 Greenwich RI   7351 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 130   2025-08-28   
401-557 7 Greenwich RI   7351 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 130   2025-08-28   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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