Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 319 [Rate centres in NPA 319] [Dial plan for NPA 319]

NXX: 404

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
319-404 A Waterloo IA CDRRIATS0MD  6266 UNITED STATES CELLULAR - IA 635      
319-404 0 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635      
319-404 1 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635      
319-404 2 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635      
319-404 3 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635      
319-404 4 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635      
319-404 5 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635      
319-404 6 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635   2011-10-29   
319-404 7 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635      
319-404 8 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635      
319-404 9 Waterloo IA   6266 UNITED STATES CELLULAR - IA 635      

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

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