Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 203 [Rate centres in NPA 203] [Dial plan for NPA 203]

NXX: 240

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-240 A Danbury CT HRFRCTASBMD  6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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