Local Calling Guide

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

NXX: 233

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
983-233 A Denver CO   597F VOIP INNOVATIONS, LLC 656   2026-07-10   

Last updated: Sun, 17 May 2026 03:26:51 UTC

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