Local Calling Guide

Area code/prefix search

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NPA: 970 [Rate centres in NPA 970] [Dial plan for NPA 970]

NXX: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
970-421 A Steamboat Springs CO DNVRCOMD4MD  6010 NEW CINGULAR WIRELESS PCS, LLC 656   2024-01-11   

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

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