Local Calling Guide

Area code/prefix search

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NPA: 303 [Rate centres in NPA 303] [Dial plan for NPA 303]

NXX: 302

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-302 A Denver CO DNVRCO37DS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 656      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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