Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 303 [Rate centres in NPA 303] [Dial plan for NPA 303]

NXX: 449

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-449 A Denver CO BLDRCOMADS0  9636 QWEST CORPORATION 656      

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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