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: 220

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
983-220 A Denver CO   053L 656   2025-09-11   
983-220 2 Denver CO   053L 656   2025-09-11   
983-220 3 Denver CO   053L 656   2025-09-11   

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

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