Local Calling Guide

Area code/prefix search

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NPA: 983 [Rate centres in NPA 983] [Dial plan for NPA 983]

NXX: 224

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
983-224 A Denver CO   671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 656   2026-04-28   
983-224 2 Denver CO   671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 656   2026-04-28   

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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