Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 720 [Rate centres in NPA 720] [Dial plan for NPA 720]

NXX: 946

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
720-946 A Denver CO DNVRCOMADS0  9636 QWEST CORPORATION 656      

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

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