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: 307

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
319-307 A Dunkerton IA CDRRIADT1MD  9877 LEVEL 3 COMMUNICATIONS, LLC - IA 635      
319-307 4 Dunkerton IA IWCYIA7000Z  490J DISH WIRELESS, LLC 635   2023-11-15   
319-307 7 Dunkerton IA CDRRIADT1MD  9877 LEVEL 3 COMMUNICATIONS, LLC - IA 635   2023-03-30   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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