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: 857

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-857 A Fort Lupton CO FTLPCOMADS0  9636 QWEST CORPORATION 656      
303-857 0 Fort Lupton CO   9636 QWEST CORPORATION 656      
303-857 1 Fort Lupton CO   9636 QWEST CORPORATION 656      
303-857 2 Fort Lupton CO   9636 QWEST CORPORATION 656      
303-857 3 Fort Lupton CO   9636 QWEST CORPORATION 656      
303-857 4 Fort Lupton CO   9636 QWEST CORPORATION 656      
303-857 5 Fort Lupton CO   6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656   2004-11-11   
303-857 6 Fort Lupton CO   9636 QWEST CORPORATION 656      
303-857 7 Fort Lupton CO   9636 QWEST CORPORATION 656      
303-857 8 Fort Lupton CO   9636 QWEST CORPORATION 656      
303-857 9 Fort Lupton CO   9636 QWEST CORPORATION 656      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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