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: 933

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
319-933 A Janesville IA CDRRIADTKMD  221F ONVOY, LLC - IA 635      
319-933 3 Janesville IA   221F ONVOY, LLC - IA 635   2021-06-11   
319-933 9 Janesville IA   221F ONVOY, LLC - IA 635   2021-09-20   

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

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