Local Calling Guide

Area code/prefix search

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NPA: 303 [Rate centres in NPA 303] [Dial plan for NPA 303]

NXX: 243

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-243 A Denver CO DNVRCOMA47Z  6874 N.E. COLORADO CELLULAR, INC. 656      
303-243 0 Denver CO   6874 N.E. COLORADO CELLULAR, INC. 656      
303-243 1 Denver CO   6874 N.E. COLORADO CELLULAR, INC. 656      
303-243 2 Denver CO   6529 T-MOBILE USA, INC. 656   2007-01-13   
303-243 3 Denver CO   3467 ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 656   2007-03-23   
303-243 4 Denver CO   6010 NEW CINGULAR WIRELESS PCS, LLC 656   2007-10-20   
303-243 5 Denver CO   829J PAETEC ITEL, LLC 656   2007-03-29   
303-243 6 Denver CO   6874 N.E. COLORADO CELLULAR, INC. 656      
303-243 7 Denver CO   6874 N.E. COLORADO CELLULAR, INC. 656      
303-243 8 Denver CO   6874 N.E. COLORADO CELLULAR, INC. 656      
303-243 9 Denver CO   6874 N.E. COLORADO CELLULAR, INC. 656      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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