Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 351 [Rate centres in NPA 351] [Dial plan for NPA 351]

NXX: 243

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
351-243 A Westford MA FRMNMAWAAMD  7421 AT&T - LOCAL 128      
351-243 0 Westford MA   6387 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 128   2025-05-30   
351-243 1 Westford MA CATNMAAKAMD  6387 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 128   2024-11-21   
351-243 8 Westford MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2024-03-03   
351-243 9 Westford MA FRMNMAWAAMD  7421 AT&T - LOCAL 128   2023-12-01   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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