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: 316

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-316 A Denver CO DNVRCOEADS0  9636 QWEST CORPORATION 656      
303-316 0 Denver CO   9636 QWEST CORPORATION 656      
303-316 1 Denver CO   732J NUSO, LLC 656   2025-08-18   
303-316 2 Denver CO   9636 QWEST CORPORATION 656      
303-316 3 Denver CO   9636 QWEST CORPORATION 656      
303-316 4 Denver CO   9636 QWEST CORPORATION 656      
303-316 5 Denver CO   9636 QWEST CORPORATION 656      
303-316 6 Denver CO   9636 QWEST CORPORATION 656      
303-316 7 Denver CO   9636 QWEST CORPORATION 656      
303-316 8 Denver CO   9636 QWEST CORPORATION 656      
303-316 9 Denver CO   9636 QWEST CORPORATION 656      

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

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