Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 475 [Rate centres in NPA 475] [Dial plan for NPA 475]

NXX: 678

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
475-678 A Danbury CT   7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920   2025-12-11   
475-678 6 Danbury CT   7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920   2025-12-11   

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

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