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: 836

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-836 A Denver CO DNVRCOKFCM1  6907 COMMUNICATIONS UNLIMITED 656      

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

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