Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 983 [Rate centres in NPA 983] [Dial plan for NPA 983]

NXX: 456

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
983-456 A Denver CO   7378 TELEPORT COMMUNICATIONS AMERICA, LLC - CO 656   2025-11-24   
983-456 6 Denver CO   7378 TELEPORT COMMUNICATIONS AMERICA, LLC - CO 656   2025-11-24   
983-456 7 Denver CO   7378 TELEPORT COMMUNICATIONS AMERICA, LLC - CO 656   2025-11-24   

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

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